From b79ad6fa5582bb1d3c6ea26d3b622cc7d3d5845d Mon Sep 17 00:00:00 2001
From: Fred Jendrzejewski <fred.jen@web.de>
Date: Fri, 16 Jan 2009 20:51:04 +1300
Subject: [PATCH] Bug 461047. Replace nsStringArray with nsTArray<nsString>.
 r+sr=roc

--HG--
extra : rebase_source : 7a20af24c97867efbb28dafa6a70ea1b4cf00e58
---
 accessible/src/base/nsAccessible.cpp          |  8 +-
 accessible/src/base/nsAccessible.h            |  5 +-
 .../base/public/nsIXPathEvaluatorInternal.h   |  3 +-
 content/base/src/nsContentSink.cpp            | 14 ++--
 content/base/src/nsContentSink.h              |  1 +
 content/base/src/nsDOMLists.cpp               | 37 +++++----
 content/base/src/nsDOMLists.h                 | 10 ++-
 content/base/src/nsDocument.cpp               | 22 +++---
 content/base/src/nsNameSpaceManager.cpp       | 18 +++--
 content/base/src/nsStyleLinkElement.cpp       |  6 +-
 content/base/src/nsStyleLinkElement.h         |  4 +-
 .../html/content/public/nsIFormProcessor.h    |  4 +-
 .../html/content/src/nsHTMLLinkElement.cpp    | 10 +--
 .../html/content/src/nsHTMLScriptElement.cpp  |  1 +
 .../html/document/src/nsHTMLContentSink.cpp   |  9 ++-
 content/xslt/src/main/txTestExpr.cpp          | 23 +++---
 content/xslt/src/xml/txDOM.h                  |  7 +-
 content/xslt/src/xml/txNodeDefinition.cpp     | 11 +--
 content/xslt/src/xpath/nsXPathEvaluator.cpp   |  8 +-
 content/xslt/src/xpath/nsXPathEvaluator.h     |  2 +-
 content/xul/templates/src/nsTemplateRule.cpp  | 14 ++--
 content/xul/templates/src/nsTemplateRule.h    |  3 +-
 dom/src/storage/nsDOMStorage.cpp              | 22 +++---
 dom/src/storage/nsDOMStorage.h                |  3 +-
 dom/src/storage/nsDOMStorageDB.cpp            | 10 +--
 dom/src/storage/nsDOMStorageDB.h              |  2 +-
 .../composer/src/nsEditorParserObserver.cpp   |  4 +-
 editor/composer/src/nsEditorParserObserver.h  |  4 +-
 editor/composer/src/nsEditorSpellCheck.cpp    | 39 ++++------
 editor/composer/src/nsEditorSpellCheck.h      |  4 +-
 editor/libeditor/html/nsHTMLCSSUtils.cpp      | 24 +++---
 editor/libeditor/html/nsHTMLCSSUtils.h        |  5 +-
 editor/libeditor/html/nsHTMLEditor.cpp        | 31 +++-----
 editor/libeditor/html/nsHTMLEditor.h          |  5 +-
 editor/txtsvc/public/nsISpellChecker.h        | 10 +--
 .../spellcheck/src/mozPersonalDictionary.cpp  | 11 ++-
 .../spellcheck/src/mozPersonalDictionary.h    |  3 +-
 extensions/spellcheck/src/mozSpellChecker.cpp | 16 ++--
 extensions/spellcheck/src/mozSpellChecker.h   | 11 +--
 gfx/src/thebes/nsThebesFontEnumerator.cpp     | 11 +--
 gfx/thebes/public/gfxBeOSPlatform.h           |  3 +-
 gfx/thebes/public/gfxOS2Platform.h            |  3 +-
 gfx/thebes/public/gfxPangoFonts.h             |  1 +
 gfx/thebes/public/gfxPlatform.h               |  3 +-
 gfx/thebes/public/gfxPlatformGtk.h            |  3 +-
 gfx/thebes/public/gfxPlatformMac.h            |  2 +-
 gfx/thebes/public/gfxQtPlatform.h             |  3 +-
 gfx/thebes/public/gfxWindowsPlatform.h        |  5 +-
 gfx/thebes/src/gfxBeOSPlatform.cpp            |  4 +-
 gfx/thebes/src/gfxFT2Fonts.cpp                | 19 ++---
 gfx/thebes/src/gfxFontconfigUtils.cpp         | 11 +--
 gfx/thebes/src/gfxFontconfigUtils.h           |  2 +-
 gfx/thebes/src/gfxOS2Fonts.cpp                | 17 +++--
 gfx/thebes/src/gfxOS2Platform.cpp             | 11 +--
 gfx/thebes/src/gfxPangoFonts.cpp              |  1 +
 gfx/thebes/src/gfxPlatform.cpp                |  3 +-
 gfx/thebes/src/gfxPlatformGtk.cpp             |  4 +-
 gfx/thebes/src/gfxPlatformMac.cpp             |  3 +-
 gfx/thebes/src/gfxQtPlatform.cpp              |  3 +-
 gfx/thebes/src/gfxQuartzFontCache.h           |  3 +-
 gfx/thebes/src/gfxQuartzFontCache.mm          |  9 ++-
 gfx/thebes/src/gfxWindowsPlatform.cpp         | 13 ++--
 intl/chardet/src/nsMetaCharsetObserver.cpp    | 52 +++++++------
 intl/chardet/src/nsMetaCharsetObserver.h      | 13 ++--
 intl/chardet/src/nsXMLEncodingObserver.h      |  5 +-
 intl/locale/src/nsLocale.cpp                  | 11 ++-
 intl/locale/src/nsLocale.h                    |  5 +-
 layout/base/nsIPresShell.h                    |  1 -
 layout/mathml/base/src/nsMathMLChar.cpp       | 22 +++---
 .../mathml/content/src/nsMathMLOperators.cpp  | 25 ++++---
 parser/htmlparser/public/nsIElementObserver.h |  5 +-
 parser/htmlparser/src/CNavDTD.cpp             |  9 +--
 parser/htmlparser/src/nsDTDUtils.cpp          | 18 ++---
 security/manager/ssl/src/nsKeygenHandler.cpp  |  4 +-
 security/manager/ssl/src/nsKeygenHandler.h    |  4 +-
 storage/src/mozStorageStatementWrapper.cpp    |  2 +-
 storage/src/mozStorageStatementWrapper.h      |  3 +-
 .../src/nsAutoCompleteSimpleResult.cpp        | 75 ++++++++-----------
 .../src/nsAutoCompleteSimpleResult.h          | 14 +++-
 .../commandlines/src/nsCommandLine.cpp        | 35 +++++----
 .../components/filepicker/src/nsFileView.cpp  |  9 ++-
 .../components/places/src/nsNavHistory.cpp    | 33 ++++----
 toolkit/components/places/src/nsNavHistory.h  |  2 +-
 .../places/src/nsNavHistoryAutoComplete.cpp   | 42 +++++------
 .../test/relicense_inputs/need_to_relicense.h |  5 +-
 tools/relic/test/relicense_inputs/npl.h       |  5 +-
 .../relicense_outputs/need_to_relicense.h     |  5 +-
 tools/relic/test/relicense_outputs/npl.h      |  5 +-
 widget/src/beos/nsDeviceContextSpecB.cpp      | 15 ++--
 widget/src/cocoa/nsFilePicker.h               |  5 +-
 widget/src/cocoa/nsFilePicker.mm              | 24 +++---
 widget/src/gtk2/nsDeviceContextSpecG.cpp      | 21 +++---
 widget/src/os2/nsDeviceContextSpecOS2.cpp     | 13 ++--
 widget/src/os2/nsFilePicker.cpp               | 24 +++---
 widget/src/os2/nsFilePicker.h                 |  5 +-
 widget/src/windows/nsDeviceContextSpecWin.cpp |  5 +-
 xpcom/ds/nsStringEnumerator.cpp               | 22 +++---
 xpcom/ds/nsStringEnumerator.h                 | 13 ++--
 xpcom/io/nsLocalFileOSX.mm                    | 11 +--
 99 files changed, 574 insertions(+), 554 deletions(-)

diff --git a/accessible/src/base/nsAccessible.cpp b/accessible/src/base/nsAccessible.cpp
index be8e086bcda..7a1dd6f606e 100644
--- a/accessible/src/base/nsAccessible.cpp
+++ b/accessible/src/base/nsAccessible.cpp
@@ -112,10 +112,10 @@ NS_IMPL_ISUPPORTS1(nsAccessibleDOMStringList, nsIDOMDOMStringList)
 NS_IMETHODIMP
 nsAccessibleDOMStringList::Item(PRUint32 aIndex, nsAString& aResult)
 {
-  if (aIndex >= (PRUint32)mNames.Count()) {
+  if (aIndex >= mNames.Length()) {
     SetDOMStringToNull(aResult);
   } else {
-    mNames.StringAt(aIndex, aResult);
+    aResult = mNames.ElementAt(aIndex);
   }
 
   return NS_OK;
@@ -124,7 +124,7 @@ nsAccessibleDOMStringList::Item(PRUint32 aIndex, nsAString& aResult)
 NS_IMETHODIMP
 nsAccessibleDOMStringList::GetLength(PRUint32 *aLength)
 {
-  *aLength = (PRUint32)mNames.Count();
+  *aLength = mNames.Length();
 
   return NS_OK;
 }
@@ -132,7 +132,7 @@ nsAccessibleDOMStringList::GetLength(PRUint32 *aLength)
 NS_IMETHODIMP
 nsAccessibleDOMStringList::Contains(const nsAString& aString, PRBool *aResult)
 {
-  *aResult = mNames.IndexOf(aString) > -1;
+  *aResult = mNames.Contains(aString);
 
   return NS_OK;
 }
diff --git a/accessible/src/base/nsAccessible.h b/accessible/src/base/nsAccessible.h
index 81c792c1244..88f3d070f22 100644
--- a/accessible/src/base/nsAccessible.h
+++ b/accessible/src/base/nsAccessible.h
@@ -55,6 +55,7 @@
 #include "nsINameSpaceManager.h"
 #include "nsWeakReference.h"
 #include "nsString.h"
+#include "nsTArray.h"
 #include "nsIDOMDOMStringList.h"
 #include "nsARIAMap.h"
 
@@ -88,11 +89,11 @@ public:
   NS_DECL_NSIDOMDOMSTRINGLIST
 
   PRBool Add(const nsAString& aName) {
-    return mNames.AppendString(aName);
+    return mNames.AppendElement(aName) != nsnull;
   }
 
 private:
-  nsStringArray mNames;
+  nsTArray<nsString> mNames;
 };
 
 
diff --git a/content/base/public/nsIXPathEvaluatorInternal.h b/content/base/public/nsIXPathEvaluatorInternal.h
index 42f8d7d1948..96593eca7e1 100644
--- a/content/base/public/nsIXPathEvaluatorInternal.h
+++ b/content/base/public/nsIXPathEvaluatorInternal.h
@@ -40,6 +40,7 @@
 #define nsIXPathEvaluatorInternal_h__
 
 #include "nsCOMArray.h"
+#include "nsTArray.h"
 
 class nsIDOMDocument;
 class nsIDOMXPathExpression;
@@ -62,7 +63,7 @@ public:
 
   NS_IMETHOD CreateExpression(const nsAString &aExpression,
                               nsIDOMXPathNSResolver *aResolver,
-                              nsStringArray *aNamespaceURIs,
+                              nsTArray<nsString> *aNamespaceURIs,
                               nsCStringArray *aContractIDs,
                               nsCOMArray<nsISupports> *aState,
                               nsIDOMXPathExpression **aResult) = 0;
diff --git a/content/base/src/nsContentSink.cpp b/content/base/src/nsContentSink.cpp
index 2f190602263..4d37e4d0fc1 100644
--- a/content/base/src/nsContentSink.cpp
+++ b/content/base/src/nsContentSink.cpp
@@ -356,7 +356,7 @@ nsContentSink::ScriptAvailable(nsresult aResult,
   // aElement will not be in mScriptElements if a <script> was added
   // using the DOM during loading, or if the script was inline and thus
   // never blocked.
-  NS_ASSERTION(mScriptElements.IndexOf(aElement) == count - 1 ||
+  NS_ASSERTION(mScriptElements.IndexOf(aElement) == PRUint32(count - 1) ||
                mScriptElements.IndexOf(aElement) == PRUint32(-1),
                "script found at unexpected position");
 
@@ -719,25 +719,25 @@ nsContentSink::ProcessLink(nsIContent* aElement,
                            const nsSubstring& aMedia)
 {
   // XXX seems overkill to generate this string array
-  nsStringArray linkTypes;
+  nsTArray<nsString> linkTypes;
   nsStyleLinkElement::ParseLinkTypes(aRel, linkTypes);
 
-  PRBool hasPrefetch = (linkTypes.IndexOf(NS_LITERAL_STRING("prefetch")) != -1);
+  PRBool hasPrefetch = linkTypes.Contains(NS_LITERAL_STRING("prefetch"));
   // prefetch href if relation is "next" or "prefetch"
-  if (hasPrefetch || linkTypes.IndexOf(NS_LITERAL_STRING("next")) != -1) {
+  if (hasPrefetch || linkTypes.Contains(NS_LITERAL_STRING("next"))) {
     PrefetchHref(aHref, aElement, hasPrefetch);
   }
 
-  if ((!aHref.IsEmpty()) && linkTypes.IndexOf(NS_LITERAL_STRING("dns-prefetch")) != -1) {
+  if ((!aHref.IsEmpty()) && linkTypes.Contains(NS_LITERAL_STRING("dns-prefetch"))) {
     PrefetchDNS(aHref);
   }
 
   // is it a stylesheet link?
-  if (linkTypes.IndexOf(NS_LITERAL_STRING("stylesheet")) == -1) {
+  if (!linkTypes.Contains(NS_LITERAL_STRING("stylesheet"))) {
     return NS_OK;
   }
 
-  PRBool isAlternate = linkTypes.IndexOf(NS_LITERAL_STRING("alternate")) != -1;
+  PRBool isAlternate = linkTypes.Contains(NS_LITERAL_STRING("alternate"));
   return ProcessStyleLink(aElement, aHref, isAlternate, aTitle, aType,
                           aMedia);
 }
diff --git a/content/base/src/nsContentSink.h b/content/base/src/nsContentSink.h
index 4d4ae47cd19..e26496bda8c 100644
--- a/content/base/src/nsContentSink.h
+++ b/content/base/src/nsContentSink.h
@@ -55,6 +55,7 @@
 #include "nsGkAtoms.h"
 #include "nsTHashtable.h"
 #include "nsHashKeys.h"
+#include "nsTArray.h"
 #include "nsITimer.h"
 #include "nsStubDocumentObserver.h"
 #include "nsIParserService.h"
diff --git a/content/base/src/nsDOMLists.cpp b/content/base/src/nsDOMLists.cpp
index ec8b5c552b6..cd610168310 100644
--- a/content/base/src/nsDOMLists.cpp
+++ b/content/base/src/nsDOMLists.cpp
@@ -69,10 +69,10 @@ NS_INTERFACE_MAP_END
 NS_IMETHODIMP
 nsDOMStringList::Item(PRUint32 aIndex, nsAString& aResult)
 {
-  if (aIndex >= (PRUint32)mNames.Count()) {
+  if (aIndex >= mNames.Length()) {
     SetDOMStringToNull(aResult);
   } else {
-    mNames.StringAt(aIndex, aResult);
+    aResult = mNames[aIndex];
   }
 
   return NS_OK;
@@ -81,7 +81,7 @@ nsDOMStringList::Item(PRUint32 aIndex, nsAString& aResult)
 NS_IMETHODIMP
 nsDOMStringList::GetLength(PRUint32 *aLength)
 {
-  *aLength = (PRUint32)mNames.Count();
+  *aLength = mNames.Length();
 
   return NS_OK;
 }
@@ -89,7 +89,7 @@ nsDOMStringList::GetLength(PRUint32 *aLength)
 NS_IMETHODIMP
 nsDOMStringList::Contains(const nsAString& aString, PRBool *aResult)
 {
-  *aResult = mNames.IndexOf(aString) > -1;
+  *aResult = mNames.Contains(aString);
 
   return NS_OK;
 }
@@ -116,10 +116,10 @@ NS_INTERFACE_TABLE_HEAD(nsNameList)
 NS_IMETHODIMP
 nsNameList::GetName(PRUint32 aIndex, nsAString& aResult)
 {
-  if (aIndex >= (PRUint32)mNames.Count()) {
+  if (aIndex >= mNames.Length()) {
     SetDOMStringToNull(aResult);
   } else {
-    mNames.StringAt(aIndex, aResult);
+    aResult = mNames[aIndex];
   }
 
   return NS_OK;
@@ -128,10 +128,10 @@ nsNameList::GetName(PRUint32 aIndex, nsAString& aResult)
 NS_IMETHODIMP
 nsNameList::GetNamespaceURI(PRUint32 aIndex, nsAString& aResult)
 {
-  if (aIndex >= (PRUint32)mNames.Count()) {
+  if (aIndex >= mNames.Length()) {
     SetDOMStringToNull(aResult);
   } else {
-    mNamespaceURIs.StringAt(aIndex, aResult);
+    aResult = mNamespaceURIs[aIndex];
   }
 
   return NS_OK;
@@ -140,7 +140,7 @@ nsNameList::GetNamespaceURI(PRUint32 aIndex, nsAString& aResult)
 NS_IMETHODIMP
 nsNameList::GetLength(PRUint32 *aLength)
 {
-  *aLength = (PRUint32)mNames.Count();
+  *aLength = mNames.Length();
 
   return NS_OK;
 }
@@ -148,12 +148,12 @@ nsNameList::GetLength(PRUint32 *aLength)
 PRBool
 nsNameList::Add(const nsAString& aNamespaceURI, const nsAString& aName)
 {
-  PRInt32 count = mNamespaceURIs.Count();
-  if (mNamespaceURIs.InsertStringAt(aNamespaceURI, count)) {
-    if (mNames.InsertStringAt(aName, count)) {
+  PRUint32 count = mNamespaceURIs.Length();
+  if (mNamespaceURIs.InsertElementAt(count, aNamespaceURI)) {
+    if (mNames.InsertElementAt(count, aName)) {
       return PR_TRUE;
     }
-    mNamespaceURIs.RemoveStringAt(count);
+    mNamespaceURIs.RemoveElementAt(count);
   }
 
   return PR_FALSE;
@@ -162,7 +162,7 @@ nsNameList::Add(const nsAString& aNamespaceURI, const nsAString& aName)
 NS_IMETHODIMP
 nsNameList::Contains(const nsAString& aName, PRBool *aResult)
 {
-  *aResult = mNames.IndexOf(aName) > -1;
+  *aResult = mNames.Contains(aName);
 
   return NS_OK;
 }
@@ -171,12 +171,9 @@ NS_IMETHODIMP
 nsNameList::ContainsNS(const nsAString& aNamespaceURI, const nsAString& aName,
                        PRBool *aResult)
 {
-  PRInt32 index = mNames.IndexOf(aName);
-  if (index > -1) {
-    nsAutoString ns;
-    mNamespaceURIs.StringAt(index, ns);
-
-    *aResult = ns.Equals(aNamespaceURI);
+  PRUint32 index = mNames.IndexOf(aName);
+  if (index != PRUint32(-1)) {
+    *aResult = mNamespaceURIs[index].Equals(aNamespaceURI);
   }
   else {
     *aResult = PR_FALSE;
diff --git a/content/base/src/nsDOMLists.h b/content/base/src/nsDOMLists.h
index 28df86df114..0be8f3ced12 100644
--- a/content/base/src/nsDOMLists.h
+++ b/content/base/src/nsDOMLists.h
@@ -48,6 +48,8 @@
 #include "nsIDOMDOMStringList.h"
 #include "nsIDOMNameList.h"
 #include "nsVoidArray.h"
+#include "nsTArray.h"
+#include "nsString.h"
 
 class nsDOMStringList : public nsIDOMDOMStringList
 {
@@ -60,11 +62,11 @@ public:
 
   PRBool Add(const nsAString& aName)
   {
-    return mNames.AppendString(aName);
+    return mNames.AppendElement(aName) != nsnull;
   }
 
 private:
-  nsStringArray mNames;
+  nsTArray<nsString> mNames;
 };
 
 class nsNameList : public nsIDOMNameList
@@ -79,8 +81,8 @@ public:
   PRBool Add(const nsAString& aNamespaceURI, const nsAString& aName);
 
 private:
-  nsStringArray mNamespaceURIs;
-  nsStringArray mNames;
+  nsTArray<nsString> mNamespaceURIs;
+  nsTArray<nsString> mNames;
 };
 
 #endif /* nsDOMLists_h___ */
diff --git a/content/base/src/nsDocument.cpp b/content/base/src/nsDocument.cpp
index f9e69678068..ab05765059e 100644
--- a/content/base/src/nsDocument.cpp
+++ b/content/base/src/nsDocument.cpp
@@ -1222,7 +1222,7 @@ public:
 
 protected:
   // Rebuild our list of style sets
-  nsresult GetSets(nsStringArray& aStyleSets);
+  nsresult GetSets(nsTArray<nsString>& aStyleSets);
   
   nsIDocument* mDocument;  // Our document; weak ref.  It'll let us know if it
                            // dies.
@@ -1247,14 +1247,14 @@ nsDOMStyleSheetSetList::nsDOMStyleSheetSetList(nsIDocument* aDocument)
 NS_IMETHODIMP
 nsDOMStyleSheetSetList::Item(PRUint32 aIndex, nsAString& aResult)
 {
-  nsStringArray styleSets;
+  nsTArray<nsString> styleSets;
   nsresult rv = GetSets(styleSets);
   NS_ENSURE_SUCCESS(rv, rv);
   
-  if (aIndex >= (PRUint32)styleSets.Count()) {
+  if (aIndex >= styleSets.Length()) {
     SetDOMStringToNull(aResult);
   } else {
-    styleSets.StringAt(aIndex, aResult);
+    aResult = styleSets[aIndex];
   }
 
   return NS_OK;
@@ -1263,11 +1263,11 @@ nsDOMStyleSheetSetList::Item(PRUint32 aIndex, nsAString& aResult)
 NS_IMETHODIMP
 nsDOMStyleSheetSetList::GetLength(PRUint32 *aLength)
 {
-  nsStringArray styleSets;
+  nsTArray<nsString> styleSets;
   nsresult rv = GetSets(styleSets);
   NS_ENSURE_SUCCESS(rv, rv);
   
-  *aLength = (PRUint32)styleSets.Count();
+  *aLength = styleSets.Length();
 
   return NS_OK;
 }
@@ -1275,17 +1275,17 @@ nsDOMStyleSheetSetList::GetLength(PRUint32 *aLength)
 NS_IMETHODIMP
 nsDOMStyleSheetSetList::Contains(const nsAString& aString, PRBool *aResult)
 {
-  nsStringArray styleSets;
+  nsTArray<nsString> styleSets;
   nsresult rv = GetSets(styleSets);
   NS_ENSURE_SUCCESS(rv, rv);
   
-  *aResult = styleSets.IndexOf(aString) != -1;
+  *aResult = styleSets.Contains(aString);
 
   return NS_OK;
 }
 
 nsresult
-nsDOMStyleSheetSetList::GetSets(nsStringArray& aStyleSets)
+nsDOMStyleSheetSetList::GetSets(nsTArray<nsString>& aStyleSets)
 {
   if (!mDocument) {
     return NS_OK; // Spec says "no exceptions", and we have no style sets if we
@@ -1299,8 +1299,8 @@ nsDOMStyleSheetSetList::GetSets(nsStringArray& aStyleSets)
     nsIStyleSheet* sheet = mDocument->GetStyleSheetAt(index);
     NS_ASSERTION(sheet, "Null sheet in sheet list!");
     sheet->GetTitle(title);
-    if (!title.IsEmpty() && aStyleSets.IndexOf(title) == -1 &&
-        !aStyleSets.AppendString(title)) {
+    if (!title.IsEmpty() && !aStyleSets.Contains(title) &&
+        !aStyleSets.AppendElement(title)) {
       return NS_ERROR_OUT_OF_MEMORY;
     }
   }
diff --git a/content/base/src/nsNameSpaceManager.cpp b/content/base/src/nsNameSpaceManager.cpp
index ac81fe90ff4..3db65e15ca5 100644
--- a/content/base/src/nsNameSpaceManager.cpp
+++ b/content/base/src/nsNameSpaceManager.cpp
@@ -45,6 +45,7 @@
 #include "nsAutoPtr.h"
 #include "nsINodeInfo.h"
 #include "nsCOMArray.h"
+#include "nsTArray.h"
 #include "nsContentCreatorFunctions.h"
 #include "nsDataHashtable.h"
 #include "nsString.h"
@@ -131,7 +132,7 @@ private:
   nsresult AddNameSpace(const nsAString& aURI, const PRInt32 aNameSpaceID);
 
   nsDataHashtable<nsNameSpaceKey,PRInt32> mURIToIDTable;
-  nsStringArray mURIArray;
+  nsTArray< nsAutoPtr<nsString> > mURIArray;
 };
 
 static NameSpaceManagerImpl* sNameSpaceManager = nsnull;
@@ -177,7 +178,7 @@ NameSpaceManagerImpl::RegisterNameSpace(const nsAString& aURI,
 
   nsresult rv = NS_OK;
   if (!mURIToIDTable.Get(&aURI, &aNameSpaceID)) {
-    aNameSpaceID = mURIArray.Count() + 1; // id is index + 1
+    aNameSpaceID = mURIArray.Length() + 1; // id is index + 1
 
     rv = AddNameSpace(aURI, aNameSpaceID);
     if (NS_FAILED(rv)) {
@@ -196,13 +197,13 @@ NameSpaceManagerImpl::GetNameSpaceURI(PRInt32 aNameSpaceID, nsAString& aURI)
   NS_PRECONDITION(aNameSpaceID >= 0, "Bogus namespace ID");
   
   PRInt32 index = aNameSpaceID - 1; // id is index + 1
-  if (index < 0 || index >= mURIArray.Count()) {
+  if (index < 0 || index >= PRInt32(mURIArray.Length())) {
     aURI.Truncate();
 
     return NS_ERROR_ILLEGAL_VALUE;
   }
 
-  mURIArray.StringAt(index, aURI);
+  aURI = *mURIArray.ElementAt(index);
 
   return NS_OK;
 }
@@ -286,16 +287,17 @@ nsresult NameSpaceManagerImpl::AddNameSpace(const nsAString& aURI,
     return NS_ERROR_OUT_OF_MEMORY;
   }
   
-  NS_ASSERTION(aNameSpaceID - 1 == mURIArray.Count(),
+  NS_ASSERTION(aNameSpaceID - 1 == mURIArray.Length(),
                "BAD! AddNameSpace not called in right order!");
 
-  if (!mURIArray.AppendString(aURI)) {
+  nsString* uri = new nsString(aURI);
+  if (!uri || !mURIArray.AppendElement(uri)) {
+    delete uri;
     return NS_ERROR_OUT_OF_MEMORY;
   }
 
-  const nsString* uri = mURIArray.StringAt(aNameSpaceID - 1);
   if (!mURIToIDTable.Put(uri, aNameSpaceID)) {
-    mURIArray.RemoveStringAt(aNameSpaceID - 1);
+    mURIArray.RemoveElementAt(aNameSpaceID - 1);
 
     return NS_ERROR_OUT_OF_MEMORY;
   }
diff --git a/content/base/src/nsStyleLinkElement.cpp b/content/base/src/nsStyleLinkElement.cpp
index a8e260d6d11..461223822ce 100644
--- a/content/base/src/nsStyleLinkElement.cpp
+++ b/content/base/src/nsStyleLinkElement.cpp
@@ -161,7 +161,7 @@ nsStyleLinkElement::SetLineNumber(PRUint32 aLineNumber)
 }
 
 void nsStyleLinkElement::ParseLinkTypes(const nsAString& aTypes,
-                                        nsStringArray& aResult)
+                                        nsTArray<nsString>& aResult)
 {
   nsAString::const_iterator start, done;
   aTypes.BeginReading(start);
@@ -177,7 +177,7 @@ void nsStyleLinkElement::ParseLinkTypes(const nsAString& aTypes,
     if (nsCRT::IsAsciiSpace(*current)) {
       if (inString) {
         ToLowerCase(Substring(start, current), subString);
-        aResult.AppendString(subString);
+        aResult.AppendElement(subString);
         inString = PR_FALSE;
       }
     }
@@ -191,7 +191,7 @@ void nsStyleLinkElement::ParseLinkTypes(const nsAString& aTypes,
   }
   if (inString) {
     ToLowerCase(Substring(start, current), subString);
-    aResult.AppendString(subString);
+    aResult.AppendElement(subString);
   }
 }
 
diff --git a/content/base/src/nsStyleLinkElement.h b/content/base/src/nsStyleLinkElement.h
index a7dd8ba9e40..21cb7be782f 100644
--- a/content/base/src/nsStyleLinkElement.h
+++ b/content/base/src/nsStyleLinkElement.h
@@ -51,9 +51,9 @@
 #include "nsIStyleSheetLinkingElement.h"
 #include "nsIStyleSheet.h"
 #include "nsIURI.h"
+#include "nsTArray.h"
 
 class nsIDocument;
-class nsStringArray;
 
 class nsStyleLinkElement : public nsIDOMLinkStyle,
                            public nsIStyleSheetLinkingElement
@@ -80,7 +80,7 @@ public:
   virtual void OverrideBaseURI(nsIURI* aNewBaseURI);
   virtual void SetLineNumber(PRUint32 aLineNumber);
 
-  static void ParseLinkTypes(const nsAString& aTypes, nsStringArray& aResult);
+  static void ParseLinkTypes(const nsAString& aTypes, nsTArray<nsString>& aResult);
 
 protected:
   /**
diff --git a/content/html/content/public/nsIFormProcessor.h b/content/html/content/public/nsIFormProcessor.h
index 1c9ec1893c3..e3b0d390f4c 100644
--- a/content/html/content/public/nsIFormProcessor.h
+++ b/content/html/content/public/nsIFormProcessor.h
@@ -49,9 +49,9 @@
 #include "prtypes.h"
 
 #include "nsIDOMHTMLInputElement.h"
+#include "nsTArray.h"
 
 class nsString;
-class nsStringArray;
 
 // {0ae53c0f-8ea2-4916-bedc-717443c3e185}
 #define NS_FORMPROCESSOR_CID \
@@ -103,7 +103,7 @@ public:
    */
 
   NS_IMETHOD ProvideContent(const nsAString& aFormType, 
-                            nsStringArray& aContent,
+                            nsTArray<nsString>& aContent,
                             nsAString& aAttribute) = 0;
 
 };
diff --git a/content/html/content/src/nsHTMLLinkElement.cpp b/content/html/content/src/nsHTMLLinkElement.cpp
index f440f53d18a..81506c2970a 100644
--- a/content/html/content/src/nsHTMLLinkElement.cpp
+++ b/content/html/content/src/nsHTMLLinkElement.cpp
@@ -304,9 +304,9 @@ nsHTMLLinkElement::SetAttr(PRInt32 aNameSpaceID, nsIAtom* aName,
     PRBool dropSheet = PR_FALSE;
     if (aNameSpaceID == kNameSpaceID_None && aName == nsGkAtoms::rel &&
         mStyleSheet) {
-      nsStringArray linkTypes(4);
+      nsAutoTArray<nsString, 4> linkTypes;
       nsStyleLinkElement::ParseLinkTypes(aValue, linkTypes);
-      dropSheet = linkTypes.IndexOf(NS_LITERAL_STRING("stylesheet")) < 0;
+      dropSheet = !linkTypes.Contains(NS_LITERAL_STRING("stylesheet"));
     }
     
     UpdateStyleSheetInternal(nsnull,
@@ -414,11 +414,11 @@ nsHTMLLinkElement::GetStyleSheetInfo(nsAString& aTitle,
   *aIsAlternate = PR_FALSE;
 
   nsAutoString rel;
-  nsStringArray linkTypes(4);
+  nsAutoTArray<nsString, 4> linkTypes;
   GetAttr(kNameSpaceID_None, nsGkAtoms::rel, rel);
   nsStyleLinkElement::ParseLinkTypes(rel, linkTypes);
   // Is it a stylesheet link?
-  if (linkTypes.IndexOf(NS_LITERAL_STRING("stylesheet")) < 0) {
+  if (!linkTypes.Contains(NS_LITERAL_STRING("stylesheet"))) {
     return;
   }
 
@@ -428,7 +428,7 @@ nsHTMLLinkElement::GetStyleSheetInfo(nsAString& aTitle,
   aTitle.Assign(title);
 
   // If alternate, does it have title?
-  if (-1 != linkTypes.IndexOf(NS_LITERAL_STRING("alternate"))) {
+  if (linkTypes.Contains(NS_LITERAL_STRING("alternate"))) {
     if (aTitle.IsEmpty()) { // alternates must have title
       return;
     } else {
diff --git a/content/html/content/src/nsHTMLScriptElement.cpp b/content/html/content/src/nsHTMLScriptElement.cpp
index f3f9affd001..b5a35ef6a21 100644
--- a/content/html/content/src/nsHTMLScriptElement.cpp
+++ b/content/html/content/src/nsHTMLScriptElement.cpp
@@ -55,6 +55,7 @@
 #include "nsIDOMDocument.h"
 #include "nsContentErrors.h"
 #include "nsIArray.h"
+#include "nsTArray.h"
 #include "nsDOMJSUtils.h"
 
 //
diff --git a/content/html/document/src/nsHTMLContentSink.cpp b/content/html/document/src/nsHTMLContentSink.cpp
index faee86c5850..2ded05afd15 100644
--- a/content/html/document/src/nsHTMLContentSink.cpp
+++ b/content/html/document/src/nsHTMLContentSink.cpp
@@ -95,6 +95,7 @@
 #include "nsIDOMHTMLMapElement.h"
 #include "nsICookieService.h"
 #include "nsVoidArray.h"
+#include "nsTArray.h"
 #include "nsIScriptSecurityManager.h"
 #include "nsIPrincipal.h"
 #include "nsTextFragment.h"
@@ -2932,17 +2933,17 @@ HTMLContentSink::ProcessLINKTag(const nsIParserNode& aNode)
       element->GetAttr(kNameSpaceID_None, nsGkAtoms::rel, relVal);
       if (!relVal.IsEmpty()) {
         // XXX seems overkill to generate this string array
-        nsStringArray linkTypes;
+        nsAutoTArray<nsString, 4> linkTypes;
         nsStyleLinkElement::ParseLinkTypes(relVal, linkTypes);
-        PRBool hasPrefetch = (linkTypes.IndexOf(NS_LITERAL_STRING("prefetch")) != -1);
-        if (hasPrefetch || linkTypes.IndexOf(NS_LITERAL_STRING("next")) != -1) {
+        PRBool hasPrefetch = linkTypes.Contains(NS_LITERAL_STRING("prefetch"));
+        if (hasPrefetch || linkTypes.Contains(NS_LITERAL_STRING("next"))) {
           nsAutoString hrefVal;
           element->GetAttr(kNameSpaceID_None, nsGkAtoms::href, hrefVal);
           if (!hrefVal.IsEmpty()) {
             PrefetchHref(hrefVal, element, hasPrefetch);
           }
         }
-        if (linkTypes.IndexOf(NS_LITERAL_STRING("dns-prefetch")) != -1) {
+        if (linkTypes.Contains(NS_LITERAL_STRING("dns-prefetch"))) {
           nsAutoString hrefVal;
           element->GetAttr(kNameSpaceID_None, nsGkAtoms::href, hrefVal);
           if (!hrefVal.IsEmpty()) {
diff --git a/content/xslt/src/main/txTestExpr.cpp b/content/xslt/src/main/txTestExpr.cpp
index bbb88341faf..0b88aa237e9 100644
--- a/content/xslt/src/main/txTestExpr.cpp
+++ b/content/xslt/src/main/txTestExpr.cpp
@@ -39,6 +39,7 @@
 #include "nsXPCOM.h"
 #include "txStandaloneXSLTProcessor.h"
 #include "nsString.h"
+#include "nsTArray.h"
 #include "txExprParser.h"
 #include "txIXPathContext.h"
 
@@ -116,27 +117,27 @@ int main(int argc, char** argv)
         return 1;
 
     nsAutoString exprOrig, expr;
-    nsStringArray exprHead, exprTail;
+    nsTArray<nsString> exprHead, exprTail;
     PRUint8 i, dropStart, dropEnd;
-    exprHead.AppendString(NS_ConvertASCIItoUTF16(kTokens[0]));
-    exprTail.AppendString(NS_ConvertASCIItoUTF16(kTokens[kCount - 1]));
+    exprHead.AppendElement(NS_ConvertASCIItoUTF16(kTokens[0]));
+    exprTail.AppendiElement(NS_ConvertASCIItoUTF16(kTokens[kCount - 1]));
     for (i = 2; i < kCount; ++i) {
-        exprHead.AppendString(*exprHead[i - 2] +
+        exprHead.AppendElement(exprHead[i - 2] +
                               NS_ConvertASCIItoUTF16(kTokens[i - 1]));
-        exprTail.AppendString(NS_ConvertASCIItoUTF16(kTokens[kCount - i]) +
-                              *exprTail[i - 2]);
+        exprTail.AppendElement(NS_ConvertASCIItoUTF16(kTokens[kCount - i]) +
+                              exprTail[i - 2]);
     }
-    exprOrig = NS_ConvertASCIItoUTF16(kTokens[0]) + *exprTail[kCount - 2];
+    exprOrig = NS_ConvertASCIItoUTF16(kTokens[0]) + exprTail[kCount - 2];
     cout << NS_LossyConvertUTF16toASCII(exprOrig).get() << endl << endl;
     for (dropStart = 0; dropStart < kCount - 2; ++dropStart) {
-        doTest(*exprTail[kCount - 2 - dropStart]);
+        doTest(exprTail[kCount - 2 - dropStart]);
         for (dropEnd = kCount - 3 - dropStart; dropEnd > 0; --dropEnd) {
-            expr = *exprHead[dropStart] + *exprTail[dropEnd];
+            expr = exprHead[dropStart] + exprTail[dropEnd];
             doTest(expr);
         }
-        doTest(*exprHead[dropStart]);
+        doTest(exprHead[dropStart]);
     }
-    doTest(*exprHead[kCount - 2]);
+    doTest(exprHead[kCount - 2]);
 
     txXSLTProcessor::shutdown();
     rv = NS_ShutdownXPCOM(nsnull);
diff --git a/content/xslt/src/xml/txDOM.h b/content/xslt/src/xml/txDOM.h
index d8c37a2d82d..5b29c118f9e 100644
--- a/content/xslt/src/xml/txDOM.h
+++ b/content/xslt/src/xml/txDOM.h
@@ -58,6 +58,7 @@
 #include "nsDoubleHashtable.h"
 #include "nsString.h"
 #include "nsVoidArray.h"
+#include "nsTArray.h"
 #include "txCore.h"
 #include "nsAutoPtr.h"
 
@@ -422,7 +423,7 @@ public:
                      "called without matching shutdown()");
         if (mNamespaces)
             return MB_TRUE;
-        mNamespaces = new nsStringArray();
+        mNamespaces = new nsTArray<nsString>();
         if (!mNamespaces)
             return MB_FALSE;
         /*
@@ -452,10 +453,10 @@ public:
     }
 
 private:
-    static nsStringArray* mNamespaces;
+    static nsTArray<nsString>* mNamespaces;
 };
 
 #define TX_IMPL_DOM_STATICS \
-    nsStringArray* txStandaloneNamespaceManager::mNamespaces = 0
+    nsTArray<nsString>* txStandaloneNamespaceManager::mNamespaces = 0
 
 #endif
diff --git a/content/xslt/src/xml/txNodeDefinition.cpp b/content/xslt/src/xml/txNodeDefinition.cpp
index 5e7271f8c6b..884b232eaff 100644
--- a/content/xslt/src/xml/txNodeDefinition.cpp
+++ b/content/xslt/src/xml/txNodeDefinition.cpp
@@ -47,6 +47,7 @@
 
 #include "txDOM.h"
 #include "nsVoidArray.h"
+#include "nsTArray.h"
 #include "txURIUtils.h"
 #include "txAtoms.h"
 #include <string.h>
@@ -225,7 +226,7 @@ Node* NodeDefinition::getXPathParent()
 nsresult NodeDefinition::getBaseURI(nsAString& aURI)
 {
   Node* node = this;
-  nsStringArray baseUrls;
+  nsTArray<nsString> baseUrls;
   nsAutoString url;
 
   while (node) {
@@ -233,12 +234,12 @@ nsresult NodeDefinition::getBaseURI(nsAString& aURI)
       case Node::ELEMENT_NODE :
         if (((Element*)node)->getAttr(txXMLAtoms::base, kNameSpaceID_XML,
                                       url))
-          baseUrls.AppendString(url);
+          baseUrls.AppendElement(url);
         break;
 
       case Node::DOCUMENT_NODE :
         node->getBaseURI(url);
-        baseUrls.AppendString(url);
+        baseUrls.AppendElement(url);
         break;
     
       default:
@@ -247,9 +248,9 @@ nsresult NodeDefinition::getBaseURI(nsAString& aURI)
     node = node->getXPathParent();
   }
 
-  PRInt32 count = baseUrls.Count();
+  PRUint32 count = baseUrls.Length();
   if (count) {
-    baseUrls.StringAt(--count, aURI);
+    aURI = baseUrls[--count];
 
     while (count > 0) {
       nsAutoString dest;
diff --git a/content/xslt/src/xpath/nsXPathEvaluator.cpp b/content/xslt/src/xpath/nsXPathEvaluator.cpp
index 0d4890d05da..1f33bbdd975 100644
--- a/content/xslt/src/xpath/nsXPathEvaluator.cpp
+++ b/content/xslt/src/xpath/nsXPathEvaluator.cpp
@@ -170,14 +170,14 @@ nsXPathEvaluator::SetDocument(nsIDOMDocument* aDocument)
 NS_IMETHODIMP
 nsXPathEvaluator::CreateExpression(const nsAString & aExpression,
                                    nsIDOMXPathNSResolver *aResolver,
-                                   nsStringArray *aNamespaceURIs,
+                                   nsTArray<nsString> *aNamespaceURIs,
                                    nsCStringArray *aContractIDs,
                                    nsCOMArray<nsISupports> *aState,
                                    nsIDOMXPathExpression **aResult)
 {
     nsTArray<PRInt32> namespaceIDs;
     if (aNamespaceURIs) {
-        PRInt32 count = aNamespaceURIs->Count();
+        PRUint32 count = aNamespaceURIs->Length();
 
         if (!aContractIDs || aContractIDs->Count() != count) {
             return NS_ERROR_FAILURE;
@@ -187,13 +187,13 @@ nsXPathEvaluator::CreateExpression(const nsAString & aExpression,
             return NS_ERROR_OUT_OF_MEMORY;
         }
 
-        PRInt32 i;
+        PRUint32 i;
         for (i = 0; i < count; ++i) {
             if (aContractIDs->CStringAt(i)->IsEmpty()) {
                 return NS_ERROR_FAILURE;
             }
 
-            nsContentUtils::NameSpaceManager()->RegisterNameSpace(*aNamespaceURIs->StringAt(i), namespaceIDs[i]);
+            nsContentUtils::NameSpaceManager()->RegisterNameSpace(aNamespaceURIs->ElementAt(i), namespaceIDs[i]);
         }
     }
 
diff --git a/content/xslt/src/xpath/nsXPathEvaluator.h b/content/xslt/src/xpath/nsXPathEvaluator.h
index 76e718b9477..8237a4b4278 100644
--- a/content/xslt/src/xpath/nsXPathEvaluator.h
+++ b/content/xslt/src/xpath/nsXPathEvaluator.h
@@ -69,7 +69,7 @@ public:
     NS_IMETHOD SetDocument(nsIDOMDocument* aDocument);
     NS_IMETHOD CreateExpression(const nsAString &aExpression, 
                                 nsIDOMXPathNSResolver *aResolver,
-                                nsStringArray *aNamespaceURIs,
+                                nsTArray<nsString> *aNamespaceURIs,
                                 nsCStringArray *aContractIDs,
                                 nsCOMArray<nsISupports> *aState,
                                 nsIDOMXPathExpression **aResult);
diff --git a/content/xul/templates/src/nsTemplateRule.cpp b/content/xul/templates/src/nsTemplateRule.cpp
index 3ff0d68a0ec..1bee90c40f4 100644
--- a/content/xul/templates/src/nsTemplateRule.cpp
+++ b/content/xul/templates/src/nsTemplateRule.cpp
@@ -76,16 +76,16 @@ nsTemplateCondition::nsTemplateCondition(nsIAtom* aSourceVariable,
         PRInt32 start = 0, end = 0;
         while ((end = aTargets.FindChar(',',start)) >= 0) {
             if (end > start) {
-                mTargetList.AppendString(Substring(aTargets, start, end - start));
+                mTargetList.AppendElement(Substring(aTargets, start, end - start));
             }
             start = end + 1;
         }
-        if (start < (PRInt32)aTargets.Length()) {
-            mTargetList.AppendString(Substring(aTargets, start));
+        if (start < PRInt32(aTargets.Length())) {
+            mTargetList.AppendElement(Substring(aTargets, start));
         }
     }
     else {
-        mTargetList.AppendString(aTargets);
+        mTargetList.AppendElement(aTargets);
     }
 
     MOZ_COUNT_CTOR(nsTemplateCondition);
@@ -150,9 +150,9 @@ nsTemplateCondition::CheckMatch(nsIXULTemplateResult* aResult)
     else {
         // iterate over the strings in the target and determine
         // whether there is a match.
-        PRInt32 length = mTargetList.Count();
-        for (PRInt32 t = 0; t < length; t++) {
-            match = CheckMatchStrings(leftString, *mTargetList[t]);
+        PRUint32 length = mTargetList.Length();
+        for (PRUint32 t = 0; t < length; t++) {
+            match = CheckMatchStrings(leftString, mTargetList[t]);
 
             // stop once a match is found. In negate mode, stop once a
             // target does not match.
diff --git a/content/xul/templates/src/nsTemplateRule.h b/content/xul/templates/src/nsTemplateRule.h
index baf49246923..fd645084cb4 100644
--- a/content/xul/templates/src/nsTemplateRule.h
+++ b/content/xul/templates/src/nsTemplateRule.h
@@ -46,6 +46,7 @@
 #include "nsIContent.h"
 #include "nsIDOMNode.h"
 #include "nsVoidArray.h"
+#include "nsTArray.h"
 #include "nsString.h"
 #include "nsIXULTemplateRuleFilter.h"
 #include "nsCycleCollectionParticipant.h"
@@ -113,7 +114,7 @@ protected:
     nsString            mSource;
     ConditionRelation   mRelation;
     nsCOMPtr<nsIAtom>   mTargetVariable;
-    nsStringArray       mTargetList;
+    nsTArray<nsString>  mTargetList;
     PRPackedBool        mIgnoreCase;
     PRPackedBool        mNegate;
 
diff --git a/dom/src/storage/nsDOMStorage.cpp b/dom/src/storage/nsDOMStorage.cpp
index 5f6a0482f1b..c6da0c36184 100644
--- a/dom/src/storage/nsDOMStorage.cpp
+++ b/dom/src/storage/nsDOMStorage.cpp
@@ -270,7 +270,7 @@ ClearStorage(nsDOMStorageEntry* aEntry, void* userArg)
 }
 
 static nsresult
-GetOfflineDomains(nsStringArray& aDomains)
+GetOfflineDomains(nsTArray<nsString>& aDomains)
 {
   nsCOMPtr<nsIPermissionManager> permissionManager =
     do_GetService(NS_PERMISSIONMANAGER_CONTRACTID);
@@ -298,7 +298,7 @@ GetOfflineDomains(nsStringArray& aDomains)
           rv = perm->GetHost(host);
           NS_ENSURE_SUCCESS(rv, rv);
 
-          aDomains.AppendString(NS_ConvertUTF8toUTF16(host));
+          aDomains.AppendElement(NS_ConvertUTF8toUTF16(host));
         }
       }
     }
@@ -327,7 +327,7 @@ nsDOMStorageManager::Observe(nsISupports *aSubject,
     NS_ENSURE_SUCCESS(rv, rv);
 
     // Remove global storage for domains that aren't marked for offline use.
-    nsStringArray domains;
+    nsTArray<nsString> domains;
     rv = GetOfflineDomains(domains);
     NS_ENSURE_SUCCESS(rv, rv);
     return nsDOMStorage::gStorageDB->RemoveOwners(domains, PR_FALSE);
@@ -353,7 +353,7 @@ nsDOMStorageManager::ClearOfflineApps()
     nsresult rv = nsDOMStorage::InitDB();
     NS_ENSURE_SUCCESS(rv, rv);
 
-    nsStringArray domains;
+    nsTArray<nsString> domains;
     rv = GetOfflineDomains(domains);
     NS_ENSURE_SUCCESS(rv, rv);
     return nsDOMStorage::gStorageDB->RemoveOwners(domains, PR_TRUE);
@@ -1215,10 +1215,10 @@ nsDOMStorageList::GetStorageForDomain(const nsAString& aRequestedDomain,
                                       PRBool aNoCurrentDomainCheck,
                                       nsresult* aResult)
 {
-  nsStringArray requestedDomainArray;
+  nsTArray<nsString> requestedDomainArray;
   if ((!aNoCurrentDomainCheck &&
        !CanAccessDomain(aRequestedDomain, aCurrentDomain)) ||
-      !ConvertDomainToArray(aRequestedDomain, &requestedDomainArray)) {
+    !ConvertDomainToArray(aRequestedDomain, &requestedDomainArray)) {
     *aResult = NS_ERROR_DOM_SECURITY_ERR;
 
     return nsnull;
@@ -1226,12 +1226,12 @@ nsDOMStorageList::GetStorageForDomain(const nsAString& aRequestedDomain,
 
   // now rebuild a string for the domain.
   nsAutoString usedDomain;
-  PRInt32 requestedPos = 0;
-  for (requestedPos = 0; requestedPos < requestedDomainArray.Count();
+  PRUint32 requestedPos = 0;
+  for (requestedPos = 0; requestedPos < requestedDomainArray.Length();
        requestedPos++) {
     if (!usedDomain.IsEmpty())
       usedDomain.AppendLiteral(".");
-    usedDomain.Append(*requestedDomainArray[requestedPos]);
+    usedDomain.Append(requestedDomainArray[requestedPos]);
   }
 
   *aResult = NS_OK;
@@ -1252,7 +1252,7 @@ nsDOMStorageList::GetStorageForDomain(const nsAString& aRequestedDomain,
 // static
 PRBool
 nsDOMStorageList::ConvertDomainToArray(const nsAString& aDomain,
-                                       nsStringArray* aArray)
+                                       nsTArray<nsString> *aArray)
 {
   PRInt32 length = aDomain.Length();
   PRInt32 n = 0;
@@ -1268,7 +1268,7 @@ nsDOMStorageList::ConvertDomainToArray(const nsAString& aDomain,
       domain.Assign(Substring(aDomain, n, dotpos - n));
 
     ToLowerCase(domain);
-    aArray->AppendString(domain);
+    aArray->AppendElement(domain);
 
     if (dotpos == -1)
       break;
diff --git a/dom/src/storage/nsDOMStorage.h b/dom/src/storage/nsDOMStorage.h
index 86d6aada3d7..8eb79229996 100644
--- a/dom/src/storage/nsDOMStorage.h
+++ b/dom/src/storage/nsDOMStorage.h
@@ -47,6 +47,7 @@
 #include "nsIDOMStorageItem.h"
 #include "nsInterfaceHashtable.h"
 #include "nsVoidArray.h"
+#include "nsTArray.h"
 #include "nsPIDOMStorage.h"
 #include "nsIDOMToString.h"
 #include "nsDOMEvent.h"
@@ -263,7 +264,7 @@ protected:
    */
   static PRBool
   ConvertDomainToArray(const nsAString& aDomain,
-                       nsStringArray* aArray);
+                       nsTArray<nsString>* aArray);
 
   nsInterfaceHashtable<nsStringHashKey, nsIDOMStorage> mStorages;
 };
diff --git a/dom/src/storage/nsDOMStorageDB.cpp b/dom/src/storage/nsDOMStorageDB.cpp
index 1babb9bc330..25885def8ee 100644
--- a/dom/src/storage/nsDOMStorageDB.cpp
+++ b/dom/src/storage/nsDOMStorageDB.cpp
@@ -440,9 +440,9 @@ nsDOMStorageDB::RemoveOwner(const nsAString& aOwner)
 
 
 nsresult
-nsDOMStorageDB::RemoveOwners(const nsStringArray &aOwners, PRBool aMatch)
+nsDOMStorageDB::RemoveOwners(const nsTArray<nsString> &aOwners, PRBool aMatch)
 {
-  if (aOwners.Count() == 0) {
+  if (aOwners.Length() == 0) {
     if (aMatch) {
       return NS_OK;
     }
@@ -460,7 +460,7 @@ nsDOMStorageDB::RemoveOwners(const nsStringArray &aOwners, PRBool aMatch)
                                          "WHERE owner NOT IN (?"));
   }
 
-  for (PRInt32 i = 1; i < aOwners.Count(); i++) {
+  for (PRUint32 i = 1; i < aOwners.Length(); i++) {
     expression.Append(", ?");
   }
   expression.Append(")");
@@ -471,8 +471,8 @@ nsDOMStorageDB::RemoveOwners(const nsStringArray &aOwners, PRBool aMatch)
                                              getter_AddRefs(statement));
   NS_ENSURE_SUCCESS(rv, rv);
 
-  for (PRInt32 i = 0; i < aOwners.Count(); i++) {
-    rv = statement->BindStringParameter(i, *aOwners[i]);
+  for (PRUint32 i = 0; i < aOwners.Length(); i++) {
+    rv = statement->BindStringParameter(i, aOwners[i]);
     NS_ENSURE_SUCCESS(rv, rv);
   }
 
diff --git a/dom/src/storage/nsDOMStorageDB.h b/dom/src/storage/nsDOMStorageDB.h
index 5ff1e475bce..b34b32ebb03 100644
--- a/dom/src/storage/nsDOMStorageDB.h
+++ b/dom/src/storage/nsDOMStorageDB.h
@@ -117,7 +117,7 @@ public:
    * list.
    */
   nsresult
-  RemoveOwners(const nsStringArray& aOwners, PRBool aMatch);
+  RemoveOwners(const nsTArray<nsString>& aOwners, PRBool aMatch);
 
   /**
    * Removes all keys from storage. Used when clearing storage.
diff --git a/editor/composer/src/nsEditorParserObserver.cpp b/editor/composer/src/nsEditorParserObserver.cpp
index 5f68d75340e..53c2a0fd341 100644
--- a/editor/composer/src/nsEditorParserObserver.cpp
+++ b/editor/composer/src/nsEditorParserObserver.cpp
@@ -89,8 +89,8 @@ NS_IMETHODIMP nsEditorParserObserver::Notify(
 NS_IMETHODIMP nsEditorParserObserver::Notify(nsISupports* aWebShell, 
                                              nsISupports* aChannel, 
                                              const PRUnichar* aTag, 
-                                             const nsStringArray* aKeys, 
-                                             const nsStringArray* aValues,
+                                             const nsTArray<nsString>* aKeys, 
+                                             const nsTArray<nsString>* aValues,
                                              const PRUint32 aFlags)
 {
   Notify();
diff --git a/editor/composer/src/nsEditorParserObserver.h b/editor/composer/src/nsEditorParserObserver.h
index 0c570720014..aa5ddc77e95 100644
--- a/editor/composer/src/nsEditorParserObserver.h
+++ b/editor/composer/src/nsEditorParserObserver.h
@@ -62,8 +62,8 @@ public:
   NS_IMETHOD                Notify(nsISupports* aWebShell, 
                                    nsISupports* aChannel,
                                    const PRUnichar* aTag, 
-                                   const nsStringArray* aKeys, 
-                                   const nsStringArray* aValues,
+                                   const nsTArray<nsString>* aKeys, 
+                                   const nsTArray<nsString>* aValues,
                                    const PRUint32 aFlags);
 
   /* methods for nsIObserver */
diff --git a/editor/composer/src/nsEditorSpellCheck.cpp b/editor/composer/src/nsEditorSpellCheck.cpp
index 270aee47c39..eeecab1d062 100644
--- a/editor/composer/src/nsEditorSpellCheck.cpp
+++ b/editor/composer/src/nsEditorSpellCheck.cpp
@@ -91,11 +91,11 @@ nsEditorSpellCheck::CanSpellCheck(PRBool* _retval)
   } else {
     spellChecker = mSpellChecker;
   }
-  nsStringArray dictList;
+  nsTArray<nsString> dictList;
   rv = spellChecker->GetDictionaryList(&dictList);
   NS_ENSURE_SUCCESS(rv, rv);
 
-  *_retval = (dictList.Count() > 0);
+  *_retval = (dictList.Length() > 0);
   return NS_OK;
 }
 
@@ -218,11 +218,11 @@ nsEditorSpellCheck::InitSpellChecker(nsIEditor* aEditor, PRBool aEnableSelection
   // locale dictionary didn't work, try to use the first dictionary we find. This helps when 
   // the first dictionary is installed
   if (! setDictionary) {
-    nsStringArray dictList;
+    nsTArray<nsString> dictList;
     rv = mSpellChecker->GetDictionaryList(&dictList);
     NS_ENSURE_SUCCESS(rv, rv);
-    if (dictList.Count() > 0) {
-      rv = SetCurrentDictionary(dictList[0]->get());
+    if (dictList.Length() > 0) {
+      rv = SetCurrentDictionary(dictList[0].get());
       if (NS_SUCCEEDED(rv))
         SaveDefaultDictionary();
     }
@@ -260,16 +260,14 @@ NS_IMETHODIMP
 nsEditorSpellCheck::GetSuggestedWord(PRUnichar **aSuggestedWord)
 {
   nsAutoString word;
-  if ( mSuggestedWordIndex < mSuggestedWordList.Count())
+  if ( mSuggestedWordIndex < PRInt32(mSuggestedWordList.Length()))
   {
-    mSuggestedWordList.StringAt(mSuggestedWordIndex, word);
+    *aSuggestedWord = ToNewUnicode(mSuggestedWordList[mSuggestedWordIndex]);
     mSuggestedWordIndex++;
   } else {
     // A blank string signals that there are no more strings
-    word.Truncate();
+    *aSuggestedWord = ToNewUnicode(EmptyString());
   }
-
-  *aSuggestedWord = ToNewUnicode(word);
   return NS_OK;
 }
 
@@ -332,17 +330,15 @@ nsEditorSpellCheck::GetPersonalDictionary()
 NS_IMETHODIMP    
 nsEditorSpellCheck::GetPersonalDictionaryWord(PRUnichar **aDictionaryWord)
 {
-  nsAutoString word;
-  if ( mDictionaryIndex < mDictionaryList.Count())
+  if ( mDictionaryIndex < PRInt32( mDictionaryList.Length()))
   {
-    mDictionaryList.StringAt(mDictionaryIndex, word);
+    *aDictionaryWord = ToNewUnicode(mDictionaryList[mDictionaryIndex]);
     mDictionaryIndex++;
   } else {
     // A blank string signals that there are no more strings
-    word.Truncate();
+    *aDictionaryWord = ToNewUnicode(EmptyString());
   }
 
-  *aDictionaryWord = ToNewUnicode(word);
   return NS_OK;
 }
 
@@ -376,7 +372,7 @@ nsEditorSpellCheck::GetDictionaryList(PRUnichar ***aDictionaryList, PRUint32 *aC
   *aDictionaryList = 0;
   *aCount          = 0;
 
-  nsStringArray dictList;
+  nsTArray<nsString> dictList;
 
   nsresult rv = mSpellChecker->GetDictionaryList(&dictList);
 
@@ -385,7 +381,7 @@ nsEditorSpellCheck::GetDictionaryList(PRUnichar ***aDictionaryList, PRUint32 *aC
 
   PRUnichar **tmpPtr = 0;
 
-  if (dictList.Count() < 1)
+  if (dictList.Length() < 1)
   {
     // If there are no dictionaries, return an array containing
     // one element and a count of one.
@@ -402,22 +398,19 @@ nsEditorSpellCheck::GetDictionaryList(PRUnichar ***aDictionaryList, PRUint32 *aC
     return NS_OK;
   }
 
-  tmpPtr = (PRUnichar **)nsMemory::Alloc(sizeof(PRUnichar *) * dictList.Count());
+  tmpPtr = (PRUnichar **)nsMemory::Alloc(sizeof(PRUnichar *) * dictList.Length());
 
   if (!tmpPtr)
     return NS_ERROR_OUT_OF_MEMORY;
 
   *aDictionaryList = tmpPtr;
-  *aCount          = dictList.Count();
-
-  nsAutoString dictStr;
+  *aCount          = dictList.Length();
 
   PRUint32 i;
 
   for (i = 0; i < *aCount; i++)
   {
-    dictList.StringAt(i, dictStr);
-    tmpPtr[i] = ToNewUnicode(dictStr);
+    tmpPtr[i] = ToNewUnicode(dictList[i]);
   }
 
   return rv;
diff --git a/editor/composer/src/nsEditorSpellCheck.h b/editor/composer/src/nsEditorSpellCheck.h
index c7c24af96c5..5d95f0c6d6d 100644
--- a/editor/composer/src/nsEditorSpellCheck.h
+++ b/editor/composer/src/nsEditorSpellCheck.h
@@ -66,12 +66,12 @@ public:
 protected:
   nsCOMPtr<nsISpellChecker> mSpellChecker;
 
-  nsStringArray  mSuggestedWordList;
+  nsTArray<nsString>  mSuggestedWordList;
   PRInt32        mSuggestedWordIndex;
 
   // these are the words in the current personal dictionary,
   // GetPersonalDictionary must be called to load them.
-  nsStringArray  mDictionaryList;
+  nsTArray<nsString>  mDictionaryList;
   PRInt32        mDictionaryIndex;
 
   nsresult       DeleteSuggestedWordList();
diff --git a/editor/libeditor/html/nsHTMLCSSUtils.cpp b/editor/libeditor/html/nsHTMLCSSUtils.cpp
index 1201484c306..4066348b25e 100644
--- a/editor/libeditor/html/nsHTMLCSSUtils.cpp
+++ b/editor/libeditor/html/nsHTMLCSSUtils.cpp
@@ -851,7 +851,7 @@ nsHTMLCSSUtils::GetCSSPropertyAtom(nsCSSEditableProperty aProperty, nsIAtom ** a
 // value aValue according to the equivalence table aEquivTable
 void
 nsHTMLCSSUtils::BuildCSSDeclarations(nsVoidArray & aPropertyArray,
-                                     nsStringArray & aValueArray,
+                                     nsTArray<nsString> & aValueArray,
                                      const CSSEquivTable * aEquivTable,
                                      const nsAString * aValue,
                                      PRBool aGetOrRemoveRequest)
@@ -883,7 +883,7 @@ nsHTMLCSSUtils::BuildCSSDeclarations(nsVoidArray & aPropertyArray,
                                                  aEquivTable[index].appendValue);
       GetCSSPropertyAtom(cssProperty, &cssPropertyAtom);
       aPropertyArray.AppendElement(cssPropertyAtom);
-      aValueArray.AppendString(cssValue);
+      aValueArray.AppendElement(cssValue);
     }
     index++;
     cssProperty = aEquivTable[index].cssProperty;
@@ -898,7 +898,7 @@ nsHTMLCSSUtils::GenerateCSSDeclarationsFromHTMLStyle(nsIDOMNode * aNode,
                                                      const nsAString * aAttribute,
                                                      const nsAString * aValue,
                                                      nsVoidArray & cssPropertyArray,
-                                                     nsStringArray & cssValueArray,
+                                                     nsTArray<nsString> & cssValueArray,
                                                      PRBool aGetOrRemoveRequest)
 {
   nsCOMPtr<nsIDOMNode> node = aNode;
@@ -1001,7 +1001,7 @@ nsHTMLCSSUtils::SetCSSEquivalentToHTMLStyle(nsIDOMNode * aNode,
 
     // Find the CSS equivalence to the HTML style
     nsVoidArray cssPropertyArray;
-    nsStringArray cssValueArray;
+    nsTArray<nsString> cssValueArray;
     GenerateCSSDeclarationsFromHTMLStyle(aNode, aHTMLProperty, aAttribute, aValue,
                                          cssPropertyArray, cssValueArray, PR_FALSE);
 
@@ -1009,11 +1009,9 @@ nsHTMLCSSUtils::SetCSSEquivalentToHTMLStyle(nsIDOMNode * aNode,
     *aCount = cssPropertyArray.Count();
     PRInt32 index;
     for (index = 0; index < *aCount; index++) {
-      nsAutoString valueString;
-      cssValueArray.StringAt(index, valueString);
       nsCOMPtr<nsIDOMElement> theElement = do_QueryInterface(aNode);
       res = SetCSSProperty(theElement, (nsIAtom *)cssPropertyArray.ElementAt(index),
-                           valueString, aSuppressTransaction);
+                           cssValueArray[index], aSuppressTransaction);
       if (NS_FAILED(res)) return res;
     }
   }
@@ -1037,7 +1035,7 @@ nsHTMLCSSUtils::RemoveCSSEquivalentToHTMLStyle(nsIDOMNode * aNode,
 
     // Find the CSS equivalence to the HTML style
     nsVoidArray cssPropertyArray;
-    nsStringArray cssValueArray;
+    nsTArray<nsString> cssValueArray;
     GenerateCSSDeclarationsFromHTMLStyle(aNode, aHTMLProperty, aAttribute, aValue,
                                          cssPropertyArray, cssValueArray, PR_TRUE);
 
@@ -1045,10 +1043,10 @@ nsHTMLCSSUtils::RemoveCSSEquivalentToHTMLStyle(nsIDOMNode * aNode,
     count = cssPropertyArray.Count();
     PRInt32 index;
     for (index = 0; index < count; index++) {
-      nsAutoString valueString;
-      cssValueArray.StringAt(index, valueString);
-      res = RemoveCSSProperty(theElement, (nsIAtom *)cssPropertyArray.ElementAt(index), valueString,
-                              aSuppressTransaction);
+      res = RemoveCSSProperty(theElement, 
+                      (nsIAtom *)cssPropertyArray.ElementAt(index), 
+                      cssValueArray[index],
+                      aSuppressTransaction);
       if (NS_FAILED(res)) return res;
     }
   }
@@ -1100,7 +1098,7 @@ nsHTMLCSSUtils::GetCSSEquivalentToHTMLInlineStyleSet(nsIDOMNode * aNode,
       if (NS_FAILED(res)) return res;
     }
     nsVoidArray cssPropertyArray;
-    nsStringArray cssValueArray;
+    nsTArray<nsString> cssValueArray;
     // get the CSS equivalence with last param PR_TRUE indicating we want only the
     // "gettable" properties
     GenerateCSSDeclarationsFromHTMLStyle(theElement, aHTMLProperty, aAttribute, nsnull,
diff --git a/editor/libeditor/html/nsHTMLCSSUtils.h b/editor/libeditor/html/nsHTMLCSSUtils.h
index 2a29ee10221..c4baf780d69 100644
--- a/editor/libeditor/html/nsHTMLCSSUtils.h
+++ b/editor/libeditor/html/nsHTMLCSSUtils.h
@@ -41,6 +41,7 @@
 
 #include "nsCOMPtr.h"
 #include "nsString.h"
+#include "nsTArray.h"
 #include "nsIDOMViewCSS.h"
 #include "nsIDOMNode.h"
 #include "nsIDOMElement.h"
@@ -341,7 +342,7 @@ private:
     */
 
   void      BuildCSSDeclarations(nsVoidArray & aPropertyArray,
-                                 nsStringArray & cssValueArray,
+                                 nsTArray<nsString> & cssValueArray,
                                  const CSSEquivTable * aEquivTable,
                                  const nsAString * aValue,
                                  PRBool aGetOrRemoveRequest);
@@ -364,7 +365,7 @@ private:
                                                  const nsAString *aAttribute,
                                                  const nsAString *aValue,
                                                  nsVoidArray & aPropertyArray,
-                                                 nsStringArray & aValueArray,
+                                                 nsTArray<nsString> & aValueArray,
                                                  PRBool aGetOrRemoveRequest);
 
   /** creates a Transaction for setting or removing a css property
diff --git a/editor/libeditor/html/nsHTMLEditor.cpp b/editor/libeditor/html/nsHTMLEditor.cpp
index a97a9a60ce9..0e382d37777 100644
--- a/editor/libeditor/html/nsHTMLEditor.cpp
+++ b/editor/libeditor/html/nsHTMLEditor.cpp
@@ -214,14 +214,9 @@ nsHTMLEditor::~nsHTMLEditor()
   // free any default style propItems
   RemoveAllDefaultProperties();
 
-  while (mStyleSheetURLs.Count())
+  while (mStyleSheetURLs.Length())
   {
-    nsAString* strp = mStyleSheetURLs.StringAt(0);
-
-    if (strp)
-    {
-      RemoveOverrideStyleSheet(*strp);
-    }
+    RemoveOverrideStyleSheet(mStyleSheetURLs[0]);
   }
 
   if (mLinkHandler && mPresShellWeak)
@@ -2184,10 +2179,8 @@ nsHTMLEditor::SetParagraphFormat(const nsAString& aParagraphFormat)
 // XXX: ERROR_HANDLING -- this method needs a little work to ensure all error codes are 
 //                        checked properly, all null pointers are checked, and no memory leaks occur
 NS_IMETHODIMP 
-nsHTMLEditor::GetParentBlockTags(nsStringArray *aTagList, PRBool aGetLists)
+nsHTMLEditor::GetParentBlockTags(nsTArray<nsString> *aTagList, PRBool aGetLists)
 {
-  if (!aTagList) { return NS_ERROR_NULL_POINTER; }
-
   nsresult res;
   nsCOMPtr<nsISelection>selection;
   res = GetSelection(getter_AddRefs(selection));
@@ -2227,7 +2220,7 @@ nsHTMLEditor::GetParentBlockTags(nsStringArray *aTagList, PRBool aGetLists)
     {
       nsAutoString blockParentTag;
       blockParentElem->GetTagName(blockParentTag);
-      aTagList->AppendString(blockParentTag);
+      aTagList->AppendElement(blockParentTag);
     }
     
     return res;
@@ -2276,8 +2269,8 @@ nsHTMLEditor::GetParentBlockTags(nsStringArray *aTagList, PRBool aGetLists)
             blockParent->GetTagName(blockParentTag);
             PRBool isRoot;
             IsRootTag(blockParentTag, isRoot);
-            if ((!isRoot) && (-1==aTagList->IndexOf(blockParentTag))) {
-              aTagList->AppendString(blockParentTag);
+            if ((!isRoot) && !aTagList->Contains(blockParentTag)) {
+              aTagList->AppendElement(blockParentTag);
             }
           }
         }
@@ -3719,12 +3712,12 @@ nsHTMLEditor::AddNewStyleSheetToList(const nsAString &aURL,
                                      nsICSSStyleSheet *aStyleSheet)
 {
   PRInt32 countSS = mStyleSheets.Count();
-  PRInt32 countU = mStyleSheetURLs.Count();
+  PRUint32 countU = mStyleSheetURLs.Length();
 
   if (countU < 0 || countSS != countU)
     return NS_ERROR_UNEXPECTED;
 
-  if (!mStyleSheetURLs.AppendString(aURL))
+  if (!mStyleSheetURLs.AppendElement(aURL))
     return NS_ERROR_UNEXPECTED;
 
   return mStyleSheets.AppendObject(aStyleSheet) ? NS_OK : NS_ERROR_UNEXPECTED;
@@ -3743,8 +3736,7 @@ nsHTMLEditor::RemoveStyleSheetFromList(const nsAString &aURL)
   nsresult rv = NS_OK;
   if (!mStyleSheets.RemoveObjectAt(foundIndex))
     rv = NS_ERROR_FAILURE;
-  if (!mStyleSheetURLs.RemoveStringAt(foundIndex))
-    rv = NS_ERROR_FAILURE;
+  mStyleSheetURLs.RemoveElementAt(foundIndex);
 
   return rv;
 }
@@ -3783,10 +3775,7 @@ nsHTMLEditor::GetURLForStyleSheet(nsICSSStyleSheet *aStyleSheet,
     return NS_OK;
 
   // Found it in the list!
-  nsAString* strp = mStyleSheetURLs.StringAt(foundIndex);
-  if (!strp)
-    return NS_ERROR_UNEXPECTED;
-  aURL = *strp;
+  aURL = mStyleSheetURLs[foundIndex];
   return NS_OK;
 }
 
diff --git a/editor/libeditor/html/nsHTMLEditor.h b/editor/libeditor/html/nsHTMLEditor.h
index cea936928b2..5f08caeacda 100644
--- a/editor/libeditor/html/nsHTMLEditor.h
+++ b/editor/libeditor/html/nsHTMLEditor.h
@@ -63,6 +63,7 @@
 #include "nsHTMLCSSUtils.h"
 
 #include "nsVoidArray.h"
+#include "nsTArray.h"
 
 #include "nsHTMLObjectResizer.h"
 #include "nsIHTMLAbsPosEditor.h"
@@ -171,7 +172,7 @@ public:
 
   NS_IMETHOD LoadHTML(const nsAString &aInputString);
 
-  NS_IMETHOD GetParentBlockTags(nsStringArray *aTagList, PRBool aGetLists);
+  NS_IMETHOD GetParentBlockTags(nsTArray<nsString> *aTagList, PRBool aGetLists);
 
   nsresult GetCSSBackgroundColorState(PRBool *aMixed, nsAString &aOutColor,
                                       PRBool aBlockLevel);
@@ -779,7 +780,7 @@ protected:
   nsString mLastOverrideStyleSheetURL;
 
   // Maintain a list of associated style sheets and their urls.
-  nsStringArray mStyleSheetURLs;
+  nsTArray<nsString> mStyleSheetURLs;
   nsCOMArray<nsICSSStyleSheet> mStyleSheets;
   
   // an array for holding default style settings
diff --git a/editor/txtsvc/public/nsISpellChecker.h b/editor/txtsvc/public/nsISpellChecker.h
index 2c2d5c09cab..66765e9f26b 100644
--- a/editor/txtsvc/public/nsISpellChecker.h
+++ b/editor/txtsvc/public/nsISpellChecker.h
@@ -39,6 +39,7 @@
 #define nsISpellChecker_h__
 
 #include "nsISupports.h"
+#include "nsTArray.h"
 
 #define NS_SPELLCHECKER_CONTRACTID "@mozilla.org/spellchecker;1"
 
@@ -49,7 +50,6 @@
 
 class nsITextServicesDocument;
 class nsString;
-class nsStringArray;
 
 /**
  * A generic interface for a spelling checker.
@@ -73,7 +73,7 @@ public:
    * @param aSuggestions is an array of nsStrings, that represent the
    * suggested replacements for the misspelled word.
    */
-  NS_IMETHOD NextMisspelledWord(nsAString &aWord, nsStringArray *aSuggestions) = 0;
+  NS_IMETHOD NextMisspelledWord(nsAString &aWord, nsTArray<nsString> *aSuggestions) = 0;
 
   /**
    * Checks if a word is misspelled. No document is required to use this method.
@@ -83,7 +83,7 @@ public:
    * suggested replacements for the misspelled word. The array will be empty
    * if there aren't any suggestions.
    */
-  NS_IMETHOD CheckWord(const nsAString &aWord, PRBool *aIsMisspelled, nsStringArray *aSuggestions) = 0;
+  NS_IMETHOD CheckWord(const nsAString &aWord, PRBool *aIsMisspelled, nsTArray<nsString> *aSuggestions) = 0;
 
   /**
    * Replaces the old word with the specified new word.
@@ -118,7 +118,7 @@ public:
    * @param aWordList is an array of nsStrings that represent the
    * list of words in the user's personal dictionary.
    */
-  NS_IMETHOD GetPersonalDictionary(nsStringArray *aWordList) = 0;
+  NS_IMETHOD GetPersonalDictionary(nsTArray<nsString> *aWordList) = 0;
 
   /**
    * Returns the list of strings representing the dictionaries
@@ -129,7 +129,7 @@ public:
    * @param aDictionaryList is an array of nsStrings that represent the
    * dictionaries supported by the spellchecker.
    */
-  NS_IMETHOD GetDictionaryList(nsStringArray *aDictionaryList) = 0;
+  NS_IMETHOD GetDictionaryList(nsTArray<nsString> *aDictionaryList) = 0;
 
   /**
    * Returns a string representing the current dictionary.
diff --git a/extensions/spellcheck/src/mozPersonalDictionary.cpp b/extensions/spellcheck/src/mozPersonalDictionary.cpp
index cb7c18de211..0ba9692173c 100644
--- a/extensions/spellcheck/src/mozPersonalDictionary.cpp
+++ b/extensions/spellcheck/src/mozPersonalDictionary.cpp
@@ -158,7 +158,7 @@ NS_IMETHODIMP mozPersonalDictionary::Load()
 static PLDHashOperator
 AddHostToStringArray(nsUniCharEntry *aEntry, void *aArg)
 {
-  static_cast<nsStringArray*>(aArg)->AppendString(nsDependentString(aEntry->GetKey()));
+  static_cast<nsTArray<nsString>*>(aArg)->AppendElement(nsDependentString(aEntry->GetKey()));
   return PL_DHASH_NEXT;
 }
 
@@ -185,14 +185,13 @@ NS_IMETHODIMP mozPersonalDictionary::Save()
   res = NS_NewBufferedOutputStream(getter_AddRefs(bufferedOutputStream), outStream, 4096);
   if (NS_FAILED(res)) return res;
 
-  nsStringArray array(mDictionaryTable.Count());
+  nsTArray<nsString> array(mDictionaryTable.Count());
   mDictionaryTable.EnumerateEntries(AddHostToStringArray, &array);
 
   PRUint32 bytesWritten;
   nsCAutoString utf8Key;
-  for (PRInt32 i = 0; i < array.Count(); ++i ) {
-    const nsString *key = array[i];
-    CopyUTF16toUTF8(*key, utf8Key);
+  for (PRInt32 i = 0; i < array.Length(); ++i ) {
+    CopyUTF16toUTF8(array[i], utf8Key);
 
     bufferedOutputStream->Write(utf8Key.get(), utf8Key.Length(), &bytesWritten);
     bufferedOutputStream->Write("\n", 1, &bytesWritten);
@@ -206,7 +205,7 @@ NS_IMETHODIMP mozPersonalDictionary::GetWordList(nsIStringEnumerator **aWords)
   NS_ENSURE_ARG_POINTER(aWords);
   *aWords = nsnull;
 
-  nsStringArray *array = new nsStringArray(mDictionaryTable.Count());
+  nsTArray<nsString> *array = new nsTArray<nsString>(mDictionaryTable.Count());
   if (!array)
     return NS_ERROR_OUT_OF_MEMORY;
 
diff --git a/extensions/spellcheck/src/mozPersonalDictionary.h b/extensions/spellcheck/src/mozPersonalDictionary.h
index ff922b749f6..876d8ed85cc 100644
--- a/extensions/spellcheck/src/mozPersonalDictionary.h
+++ b/extensions/spellcheck/src/mozPersonalDictionary.h
@@ -46,6 +46,7 @@
 #include "nsIObserver.h"
 #include "nsWeakReference.h"
 #include "nsTHashtable.h"
+#include "nsTArray.h"
 #include "nsCRT.h"
 
 #define MOZ_PERSONALDICTIONARY_CONTRACTID "@mozilla.org/spellchecker/personaldictionary;1"
@@ -101,7 +102,7 @@ public:
   nsresult Init();
 
 protected:
-  nsStringArray  mDictionary;  /* use something a little smarter eventually*/
+  nsTArray<nsString>  mDictionary;  /* use something a little smarter eventually*/
   PRBool         mDirty;       /* has the dictionary been modified */
   nsTHashtable<nsUniCharEntry> mDictionaryTable;
   nsTHashtable<nsUniCharEntry> mIgnoreTable;
diff --git a/extensions/spellcheck/src/mozSpellChecker.cpp b/extensions/spellcheck/src/mozSpellChecker.cpp
index c4544067b40..b4939025a6c 100644
--- a/extensions/spellcheck/src/mozSpellChecker.cpp
+++ b/extensions/spellcheck/src/mozSpellChecker.cpp
@@ -84,7 +84,7 @@ mozSpellChecker::SetDocument(nsITextServicesDocument *aDoc, PRBool aFromStartofD
 
 
 NS_IMETHODIMP 
-mozSpellChecker::NextMisspelledWord(nsAString &aWord, nsStringArray *aSuggestions)
+mozSpellChecker::NextMisspelledWord(nsAString &aWord, nsTArray<nsString> *aSuggestions)
 {
   if(!aSuggestions||!mConverter)
     return NS_ERROR_NULL_POINTER;
@@ -128,7 +128,7 @@ mozSpellChecker::NextMisspelledWord(nsAString &aWord, nsStringArray *aSuggestion
 }
 
 NS_IMETHODIMP 
-mozSpellChecker::CheckWord(const nsAString &aWord, PRBool *aIsMisspelled, nsStringArray *aSuggestions)
+mozSpellChecker::CheckWord(const nsAString &aWord, PRBool *aIsMisspelled, nsTArray<nsString> *aSuggestions)
 {
   nsresult result;
   PRBool correct;
@@ -152,7 +152,7 @@ mozSpellChecker::CheckWord(const nsAString &aWord, PRBool *aIsMisspelled, nsStri
       result = mSpellCheckingEngine->Suggest(PromiseFlatString(aWord).get(), &words, &count);
       NS_ENSURE_SUCCESS(result, result); 
       for(i=0;i<count;i++){
-        aSuggestions->AppendString(nsDependentString(words[i]));
+        aSuggestions->AppendElement(nsDependentString(words[i]));
       }
       
       if (count)
@@ -287,7 +287,7 @@ mozSpellChecker::RemoveWordFromPersonalDictionary(const nsAString &aWord)
 }
 
 NS_IMETHODIMP 
-mozSpellChecker::GetPersonalDictionary(nsStringArray *aWordList)
+mozSpellChecker::GetPersonalDictionary(nsTArray<nsString> *aWordList)
 {
   if(!aWordList || !mPersonalDictionary)
     return NS_ERROR_NULL_POINTER;
@@ -299,14 +299,14 @@ mozSpellChecker::GetPersonalDictionary(nsStringArray *aWordList)
   nsAutoString word;
   while (NS_SUCCEEDED(words->HasMore(&hasMore)) && hasMore) {
     words->GetNext(word);
-    aWordList->AppendString(word);
+    aWordList->AppendElement(word);
   }
   return NS_OK;
 }
 
 struct AppendNewStruct
 {
-  nsStringArray *dictionaryList;
+  nsTArray<nsString> *dictionaryList;
   PRBool failed;
 };
 
@@ -315,7 +315,7 @@ AppendNewString(const nsAString& aString, nsCString*, void* aClosure)
 {
   AppendNewStruct *ans = (AppendNewStruct*) aClosure;
 
-  if (!ans->dictionaryList->AppendString(aString))
+  if (!ans->dictionaryList->AppendElement(aString))
   {
     ans->failed = PR_TRUE;
     return PL_DHASH_STOP;
@@ -325,7 +325,7 @@ AppendNewString(const nsAString& aString, nsCString*, void* aClosure)
 }
 
 NS_IMETHODIMP 
-mozSpellChecker::GetDictionaryList(nsStringArray *aDictionaryList)
+mozSpellChecker::GetDictionaryList(nsTArray<nsString> *aDictionaryList)
 {
   AppendNewStruct ans = {aDictionaryList, PR_FALSE};
 
diff --git a/extensions/spellcheck/src/mozSpellChecker.h b/extensions/spellcheck/src/mozSpellChecker.h
index 098811f4c0d..9d67e4c6ae0 100644
--- a/extensions/spellcheck/src/mozSpellChecker.h
+++ b/extensions/spellcheck/src/mozSpellChecker.h
@@ -46,6 +46,7 @@
 #include "mozISpellCheckingEngine.h"
 #include "nsClassHashtable.h"
 #include "nsVoidArray.h"
+#include "nsTArray.h"
 #include "mozISpellI18NUtil.h"
 
 class mozSpellChecker : public nsISpellChecker
@@ -60,16 +61,16 @@ public:
 
   // nsISpellChecker
   NS_IMETHOD SetDocument(nsITextServicesDocument *aDoc, PRBool aFromStartofDoc);
-  NS_IMETHOD NextMisspelledWord(nsAString &aWord, nsStringArray *aSuggestions);
-  NS_IMETHOD CheckWord(const nsAString &aWord, PRBool *aIsMisspelled, nsStringArray *aSuggestions);
+  NS_IMETHOD NextMisspelledWord(nsAString &aWord, nsTArray<nsString> *aSuggestions);
+  NS_IMETHOD CheckWord(const nsAString &aWord, PRBool *aIsMisspelled, nsTArray<nsString> *aSuggestions);
   NS_IMETHOD Replace(const nsAString &aOldWord, const nsAString &aNewWord, PRBool aAllOccurrences);
   NS_IMETHOD IgnoreAll(const nsAString &aWord);
 
   NS_IMETHOD AddWordToPersonalDictionary(const nsAString &aWord);
   NS_IMETHOD RemoveWordFromPersonalDictionary(const nsAString &aWord);
-  NS_IMETHOD GetPersonalDictionary(nsStringArray *aWordList);
+  NS_IMETHOD GetPersonalDictionary(nsTArray<nsString> *aWordList);
 
-  NS_IMETHOD GetDictionaryList(nsStringArray *aDictionaryList);
+  NS_IMETHOD GetDictionaryList(nsTArray<nsString> *aDictionaryList);
   NS_IMETHOD GetCurrentDictionary(nsAString &aDictionary);
   NS_IMETHOD SetCurrentDictionary(const nsAString &aDictionary);
 
@@ -85,7 +86,7 @@ protected:
   nsCString *mCurrentEngineContractId;
   nsCOMPtr<mozISpellCheckingEngine>  mSpellCheckingEngine;
   PRBool mFromStart;
-  nsStringArray mIgnoreList;
+  nsTArray<nsString> mIgnoreList;
 
   nsresult SetupDoc(PRUint32 *outBlockOffset);
 
diff --git a/gfx/src/thebes/nsThebesFontEnumerator.cpp b/gfx/src/thebes/nsThebesFontEnumerator.cpp
index d6cc492a05a..597b5cef48b 100644
--- a/gfx/src/thebes/nsThebesFontEnumerator.cpp
+++ b/gfx/src/thebes/nsThebesFontEnumerator.cpp
@@ -41,6 +41,7 @@
 #include "nsMemory.h"
 
 #include "gfxPlatform.h"
+#include "nsTArray.h"
 
 NS_IMPL_ISUPPORTS1(nsThebesFontEnumerator, nsIFontEnumerator)
 
@@ -64,7 +65,7 @@ nsThebesFontEnumerator::EnumerateFonts(const char *aLangGroup,
     NS_ENSURE_ARG_POINTER(aCount);
     NS_ENSURE_ARG_POINTER(aResult);
 
-    nsStringArray fontList;
+    nsTArray<nsString> fontList;
 
     nsCAutoString langGroup;
     nsCAutoString generic;
@@ -89,13 +90,13 @@ nsThebesFontEnumerator::EnumerateFonts(const char *aLangGroup,
     }
 
     PRUnichar **fs = static_cast<PRUnichar **>
-                                (nsMemory::Alloc(fontList.Count() * sizeof(PRUnichar*)));
-    for (int i = 0; i < fontList.Count(); i++) {
-        fs[i] = ToNewUnicode(*fontList[i]);
+                                (nsMemory::Alloc(fontList.Length() * sizeof(PRUnichar*)));
+    for (PRUint32 i = 0; i < fontList.Length(); i++) {
+        fs[i] = ToNewUnicode(fontList[i]);
     }
 
     *aResult = fs;
-    *aCount = fontList.Count();
+    *aCount = fontList.Length();
 
     return NS_OK;
 }
diff --git a/gfx/thebes/public/gfxBeOSPlatform.h b/gfx/thebes/public/gfxBeOSPlatform.h
index 8cc68783a73..9593690bae1 100644
--- a/gfx/thebes/public/gfxBeOSPlatform.h
+++ b/gfx/thebes/public/gfxBeOSPlatform.h
@@ -40,6 +40,7 @@
 #define GFX_PLATFORM_BEOS_H
 
 #include "gfxPlatform.h"
+#include "gfxTArray.h"
 
 class gfxFontconfigUtils;
 
@@ -59,7 +60,7 @@ public:
 
     nsresult GetFontList(const nsACString& aLangGroup,
                          const nsACString& aGenericFamily,
-                         nsStringArray& aListOfFonts);
+                         nsTArray<nsString>& aListOfFonts);
 
     nsresult UpdateFontList();
 
diff --git a/gfx/thebes/public/gfxOS2Platform.h b/gfx/thebes/public/gfxOS2Platform.h
index 4aba2eb8e19..f84ee818ef9 100644
--- a/gfx/thebes/public/gfxOS2Platform.h
+++ b/gfx/thebes/public/gfxOS2Platform.h
@@ -44,6 +44,7 @@
 #include "gfxPlatform.h"
 #include "gfxOS2Fonts.h"
 #include "gfxFontUtils.h"
+#include "nsTArray.h"
 
 class gfxFontconfigUtils;
 
@@ -63,7 +64,7 @@ public:
 
     nsresult GetFontList(const nsACString& aLangGroup,
                          const nsACString& aGenericFamily,
-                         nsStringArray& aListOfFonts);
+                         nsTArray<nsString>& aListOfFonts);
     nsresult UpdateFontList();
     nsresult ResolveFontName(const nsAString& aFontName,
                              FontResolverCallback aCallback,
diff --git a/gfx/thebes/public/gfxPangoFonts.h b/gfx/thebes/public/gfxPangoFonts.h
index 2cced879dcd..ebec2d366bc 100644
--- a/gfx/thebes/public/gfxPangoFonts.h
+++ b/gfx/thebes/public/gfxPangoFonts.h
@@ -44,6 +44,7 @@
 #include "gfxFont.h"
 
 #include "nsAutoRef.h"
+#include "nsTArray.h"
 
 #include <pango/pango.h>
 
diff --git a/gfx/thebes/public/gfxPlatform.h b/gfx/thebes/public/gfxPlatform.h
index addcee63263..04bb8e5f55e 100644
--- a/gfx/thebes/public/gfxPlatform.h
+++ b/gfx/thebes/public/gfxPlatform.h
@@ -41,6 +41,7 @@
 
 #include "prtypes.h"
 #include "nsVoidArray.h"
+#include "nsTArray.h"
 
 #include "nsIObserver.h"
 
@@ -158,7 +159,7 @@ public:
      */
     virtual nsresult GetFontList(const nsACString& aLangGroup,
                                  const nsACString& aGenericFamily,
-                                 nsStringArray& aListOfFonts);
+                                 nsTArray<nsString>& aListOfFonts);
 
     /**
      * Rebuilds the any cached system font lists
diff --git a/gfx/thebes/public/gfxPlatformGtk.h b/gfx/thebes/public/gfxPlatformGtk.h
index 08227f91177..eed910a5ccf 100644
--- a/gfx/thebes/public/gfxPlatformGtk.h
+++ b/gfx/thebes/public/gfxPlatformGtk.h
@@ -41,6 +41,7 @@
 
 #include "gfxPlatform.h"
 #include "nsAutoRef.h"
+#include "nsTArray.h"
 
 extern "C" {
     typedef struct _GdkDrawable GdkDrawable;
@@ -74,7 +75,7 @@ public:
 
     nsresult GetFontList(const nsACString& aLangGroup,
                          const nsACString& aGenericFamily,
-                         nsStringArray& aListOfFonts);
+                         nsTArray<nsString>& aListOfFonts);
 
     nsresult UpdateFontList();
 
diff --git a/gfx/thebes/public/gfxPlatformMac.h b/gfx/thebes/public/gfxPlatformMac.h
index e09ef09c2ea..f6bfa4d6b58 100644
--- a/gfx/thebes/public/gfxPlatformMac.h
+++ b/gfx/thebes/public/gfxPlatformMac.h
@@ -81,7 +81,7 @@ public:
 
     nsresult GetFontList(const nsACString& aLangGroup,
                          const nsACString& aGenericFamily,
-                         nsStringArray& aListOfFonts);
+                         nsTArray<nsString>& aListOfFonts);
     nsresult UpdateFontList();
 
     // in some situations, need to make decisions about ambiguous characters, may need to look at multiple pref langs
diff --git a/gfx/thebes/public/gfxQtPlatform.h b/gfx/thebes/public/gfxQtPlatform.h
index 469959dfd45..e602336b08e 100644
--- a/gfx/thebes/public/gfxQtPlatform.h
+++ b/gfx/thebes/public/gfxQtPlatform.h
@@ -41,6 +41,7 @@
 
 #include "gfxPlatform.h"
 #include "nsDataHashtable.h"
+#include "nsTArray.h"
 
 typedef struct FT_LibraryRec_ *FT_Library;
 
@@ -62,7 +63,7 @@ public:
 
     nsresult GetFontList(const nsACString& aLangGroup,
                          const nsACString& aGenericFamily,
-                         nsStringArray& aListOfFonts);
+                         nsTArray<nsString>& aListOfFonts);
 
     nsresult UpdateFontList();
 
diff --git a/gfx/thebes/public/gfxWindowsPlatform.h b/gfx/thebes/public/gfxWindowsPlatform.h
index b1698eb5201..10b600c6f24 100644
--- a/gfx/thebes/public/gfxWindowsPlatform.h
+++ b/gfx/thebes/public/gfxWindowsPlatform.h
@@ -45,6 +45,7 @@
 #include "gfxPlatform.h"
 
 #include "nsVoidArray.h"
+#include "nsTArray.h"
 #include "nsDataHashtable.h"
 
 #include <windows.h>
@@ -62,7 +63,7 @@ public:
 
     nsresult GetFontList(const nsACString& aLangGroup,
                          const nsACString& aGenericFamily,
-                         nsStringArray& aListOfFonts);
+                         nsTArray<nsString>& aListOfFonts);
 
     nsresult UpdateFontList();
 
@@ -159,7 +160,7 @@ private:
     FontTable mFonts;
     FontTable mFontAliases;
     FontTable mFontSubstitutes;
-    nsStringArray mNonExistingFonts;
+    nsTArray<nsString> mNonExistingFonts;
 
     // when system-wide font lookup fails for a character, cache it to skip future searches
     gfxSparseBitSet mCodepointsWithNoFonts;
diff --git a/gfx/thebes/src/gfxBeOSPlatform.cpp b/gfx/thebes/src/gfxBeOSPlatform.cpp
index f71ef74ddb0..5aa0b22d6b9 100644
--- a/gfx/thebes/src/gfxBeOSPlatform.cpp
+++ b/gfx/thebes/src/gfxBeOSPlatform.cpp
@@ -42,6 +42,8 @@
 #include "gfxImageSurface.h"
 #include "gfxBeOSSurface.h"
 
+#include "nsTArray.h"
+
 gfxFontconfigUtils *gfxPlatformGtk::sFontconfigUtils = nsnull;
 
 gfxBeOSPlatform::gfxBeOSPlatform()
@@ -88,7 +90,7 @@ gfxBeOSPlatform::CreateOffscreenSurface (PRUint32 width,
 nsresult
 gfxBeOSPlatform::GetFontList(const nsACString& aLangGroup,
                              const nsACString& aGenericFamily,
-                             nsStringArray& aListOfFonts)
+                             nsTArray<nsString>& aListOfFonts)
 {
     return sFontconfigUtils->GetFontList(aLangGroup, aGenericFamily,
                                          aListOfFonts);
diff --git a/gfx/thebes/src/gfxFT2Fonts.cpp b/gfx/thebes/src/gfxFT2Fonts.cpp
index d792f8afc01..51c84a15bb6 100644
--- a/gfx/thebes/src/gfxFT2Fonts.cpp
+++ b/gfx/thebes/src/gfxFT2Fonts.cpp
@@ -48,6 +48,7 @@
 #include "cairo-ft.h"
 #include <freetype/tttables.h>
 #include "gfxFontUtils.h"
+#include "nsTArray.h"
 
 /**
  * FontEntry
@@ -177,10 +178,10 @@ gfxFT2FontGroup::FontCallback(const nsAString& fontName,
                              const nsACString& genericName,
                              void *closure)
 {
-    nsStringArray *sa = static_cast<nsStringArray*>(closure);
+    nsTArray<nsString> *sa = static_cast<nsTArray<nsString>*>(closure);
 
-    if (!fontName.IsEmpty() && sa->IndexOf(fontName) < 0) {
-        sa->AppendString(fontName);
+    if (!fontName.IsEmpty() && !sa->Contains(fontName)) {
+        sa->AppendElement(fontName);
 #ifdef DEBUG_pavlov
         printf(" - %s\n", NS_ConvertUTF16toUTF8(fontName).get());
 #endif
@@ -223,10 +224,10 @@ gfxFT2FontGroup::gfxFT2FontGroup(const nsAString& families,
 #ifdef DEBUG_pavlov
     printf("Looking for %s\n", NS_ConvertUTF16toUTF8(families).get());
 #endif
-    nsStringArray familyArray;
+    nsTArray<nsString> familyArray;
     ForEachFont(FontCallback, &familyArray);
 
-    if (familyArray.Count() == 0) {
+    if (familyArray.Length() == 0) {
         nsAutoString prefFamilies;
         gfxToolkitPlatform::GetPlatform()->GetPrefFonts(aStyle->langGroup.get(), prefFamilies, nsnull);
         if (!prefFamilies.IsEmpty()) {
@@ -234,17 +235,17 @@ gfxFT2FontGroup::gfxFT2FontGroup(const nsAString& families,
         }
     }
 #if defined(MOZ_WIDGET_QT) /* FIXME DFB */
-    if (familyArray.Count() == 0) {
+    if (familyArray.Length() == 0) {
         printf("failde to find a font. sadface\n");
         // We want to get rid of this entirely at some point, but first we need real lists of fonts.
         QFont defaultFont;
         QFontInfo fi (defaultFont);
-        familyArray.AppendString(nsDependentString(static_cast<const PRUnichar *>(fi.family().utf16())));
+        familyArray.AppendElement(nsDependentString(static_cast<const PRUnichar *>(fi.family().utf16())));
     }
 #endif
 
-    for (int i = 0; i < familyArray.Count(); i++) {
-        nsRefPtr<gfxFT2Font> font = GetOrMakeFont(*familyArray[i], &mStyle);
+    for (PRUint32 i = 0; i < familyArray.Length(); i++) {
+        nsRefPtr<gfxFT2Font> font = GetOrMakeFont(familyArray[i], &mStyle);
         if (font) {
             mFonts.AppendElement(font);
         }
diff --git a/gfx/thebes/src/gfxFontconfigUtils.cpp b/gfx/thebes/src/gfxFontconfigUtils.cpp
index 9f0ce14d454..a849764a557 100644
--- a/gfx/thebes/src/gfxFontconfigUtils.cpp
+++ b/gfx/thebes/src/gfxFontconfigUtils.cpp
@@ -47,6 +47,7 @@
 #include "nsIPrefService.h"
 #include "nsServiceManagerUtils.h"
 #include "nsILanguageAtomService.h"
+#include "nsTArray.h"
 
 #include "nsIAtom.h"
 #include "nsCRT.h"
@@ -273,7 +274,7 @@ gfxFontconfigUtils::gfxFontconfigUtils()
 nsresult
 gfxFontconfigUtils::GetFontList(const nsACString& aLangGroup,
                                 const nsACString& aGenericFamily,
-                                nsStringArray& aListOfFonts)
+                                nsTArray<nsString>& aListOfFonts)
 {
     aListOfFonts.Clear();
 
@@ -283,7 +284,7 @@ gfxFontconfigUtils::GetFontList(const nsACString& aLangGroup,
         return rv;
 
     for (PRInt32 i = 0; i < fonts.Count(); ++i) {
-        aListOfFonts.AppendString(NS_ConvertUTF8toUTF16(*fonts.CStringAt(i)));
+        aListOfFonts.AppendElement(NS_ConvertUTF8toUTF16(*fonts.CStringAt(i)));
     }
 
     aListOfFonts.Sort();
@@ -310,11 +311,11 @@ gfxFontconfigUtils::GetFontList(const nsACString& aLangGroup,
     // gFontsDialog.readFontSelection() if the preference-selected font is not
     // available, so put system configured defaults first.
     if (monospace)
-        aListOfFonts.InsertStringAt(NS_LITERAL_STRING("monospace"), 0);
+        aListOfFonts.InsertElementAt(0, NS_LITERAL_STRING("monospace"));
     if (sansSerif)
-        aListOfFonts.InsertStringAt(NS_LITERAL_STRING("sans-serif"), 0);
+        aListOfFonts.InsertElementAt(0, NS_LITERAL_STRING("sans-serif"));
     if (serif)
-        aListOfFonts.InsertStringAt(NS_LITERAL_STRING("serif"), 0);
+        aListOfFonts.InsertElementAt(0, NS_LITERAL_STRING("serif"));
 
     return NS_OK;
 }
diff --git a/gfx/thebes/src/gfxFontconfigUtils.h b/gfx/thebes/src/gfxFontconfigUtils.h
index 664146d698c..7b62c8419d0 100644
--- a/gfx/thebes/src/gfxFontconfigUtils.h
+++ b/gfx/thebes/src/gfxFontconfigUtils.h
@@ -92,7 +92,7 @@ public:
 
     nsresult GetFontList(const nsACString& aLangGroup,
                          const nsACString& aGenericFamily,
-                         nsStringArray& aListOfFonts);
+                         nsTArray<nsString>& aListOfFonts);
 
     nsresult UpdateFontList();
 
diff --git a/gfx/thebes/src/gfxOS2Fonts.cpp b/gfx/thebes/src/gfxOS2Fonts.cpp
index ca48dc1f607..3f8ff5798e8 100644
--- a/gfx/thebes/src/gfxOS2Fonts.cpp
+++ b/gfx/thebes/src/gfxOS2Fonts.cpp
@@ -44,6 +44,7 @@
 #include "gfxOS2Platform.h"
 #include "gfxOS2Surface.h"
 #include "gfxOS2Fonts.h"
+#include "nsTArray.h"
 
 #include "nsIServiceManager.h"
 #include "nsIPlatformCharset.h"
@@ -483,7 +484,7 @@ gfxOS2FontGroup::gfxOS2FontGroup(const nsAString& aFamilies,
         mFamilies.Replace(pos, 8, NS_LITERAL_STRING("Workplace Sans"));
     }
 
-    nsStringArray familyArray;
+    nsTArray<nsString> familyArray;
     ForEachFont(FontCallback, &familyArray);
 
     // To be able to easily search for glyphs in other fonts, append a few good
@@ -499,12 +500,12 @@ gfxOS2FontGroup::gfxOS2FontGroup(const nsAString& aFamilies,
     // Should append some default font if there are no available fonts.
     // Let's use Helv which should be available on any OS/2 system; if
     // it's not there, Fontconfig replaces it with something else...
-    if (familyArray.Count() == 0) {
-        familyArray.AppendString(NS_LITERAL_STRING("Helv"));
+    if (familyArray.Length() == 0) {
+        familyArray.AppendElement(NS_LITERAL_STRING("Helv"));
     }
 
-    for (int i = 0; i < familyArray.Count(); i++) {
-        nsRefPtr<gfxOS2Font> font = gfxOS2Font::GetOrMakeFont(*familyArray[i], &mStyle);
+    for (PRUint32 i = 0; i < familyArray.Length(); i++) {
+        nsRefPtr<gfxOS2Font> font = gfxOS2Font::GetOrMakeFont(familyArray[i], &mStyle);
         if (font) {
             mFonts.AppendElement(font);
         }
@@ -820,9 +821,9 @@ PRBool gfxOS2FontGroup::FontCallback(const nsAString& aFontName,
                                      const nsACString& aGenericName,
                                      void *aClosure)
 {
-    nsStringArray *sa = static_cast<nsStringArray*>(aClosure);
-    if (!aFontName.IsEmpty() && sa->IndexOf(aFontName) < 0) {
-        sa->AppendString(aFontName);
+    nsTArray<nsString> *sa = static_cast<nsTArray<nsString>*>(aClosure);
+    if (!aFontName.IsEmpty() && !sa->Contains(aFontName)) {
+        sa->AppendElement(aFontName);
     }
     return PR_TRUE;
 }
diff --git a/gfx/thebes/src/gfxOS2Platform.cpp b/gfx/thebes/src/gfxOS2Platform.cpp
index d1d7e597b49..1e49f4302ce 100644
--- a/gfx/thebes/src/gfxOS2Platform.cpp
+++ b/gfx/thebes/src/gfxOS2Platform.cpp
@@ -41,6 +41,7 @@
 #include "gfxOS2Surface.h"
 #include "gfxImageSurface.h"
 #include "gfxOS2Fonts.h"
+#include "nsTArray.h"
 
 #include "gfxFontconfigUtils.h"
 //#include <fontconfig/fontconfig.h>
@@ -111,7 +112,7 @@ gfxOS2Platform::CreateOffscreenSurface(const gfxIntSize& aSize,
 nsresult
 gfxOS2Platform::GetFontList(const nsACString& aLangGroup,
                             const nsACString& aGenericFamily,
-                            nsStringArray& aListOfFonts)
+                            nsTArray<nsString>& aListOfFonts)
 {
 #ifdef DEBUG_thebes
     char *langgroup = ToNewCString(aLangGroup),
@@ -184,18 +185,18 @@ gfxOS2Platform::FindFontForChar(PRUint32 aCh, gfxOS2Font *aFont)
     // (one should instead cache the charmaps as done on Mac and Win)
 
     // just continue to append all fonts known to the system
-    nsStringArray fontList;
+    nsTArray<nsString> fontList;
     nsCAutoString generic;
     nsresult rv = GetFontList(aFont->GetStyle()->langGroup, generic, fontList);
     if (NS_SUCCEEDED(rv)) {
         // start at 3 to skip over the generic entries
-        for (int i = 3; i < fontList.Count(); i++) {
+        for (PRUint32 i = 3; i < fontList.Length(); i++) {
 #ifdef DEBUG_thebes
             printf("searching in entry i=%d (%s)\n",
-                   i, NS_LossyConvertUTF16toASCII(*fontList[i]).get());
+                   i, NS_LossyConvertUTF16toASCII(fontList[i]).get());
 #endif
             nsRefPtr<gfxOS2Font> font =
-                gfxOS2Font::GetOrMakeFont(*fontList[i], aFont->GetStyle());
+                gfxOS2Font::GetOrMakeFont(fontList[i], aFont->GetStyle());
             if (!font)
                 continue;
             FT_Face face = cairo_ft_scaled_font_lock_face(font->CairoScaledFont());
diff --git a/gfx/thebes/src/gfxPangoFonts.cpp b/gfx/thebes/src/gfxPangoFonts.cpp
index e23caeab616..9115bbba651 100644
--- a/gfx/thebes/src/gfxPangoFonts.cpp
+++ b/gfx/thebes/src/gfxPangoFonts.cpp
@@ -49,6 +49,7 @@
 #include "gfxTypes.h"
 
 #include "nsMathUtils.h"
+#include "nsTArray.h"
 #include "nsServiceManagerUtils.h"
 #include "nsILanguageAtomService.h"
 
diff --git a/gfx/thebes/src/gfxPlatform.cpp b/gfx/thebes/src/gfxPlatform.cpp
index ae155351e71..7c3d6638f1e 100644
--- a/gfx/thebes/src/gfxPlatform.cpp
+++ b/gfx/thebes/src/gfxPlatform.cpp
@@ -60,6 +60,7 @@
 
 #include "nsIPref.h"
 #include "nsServiceManagerUtils.h"
+#include "nsTArray.h"
 
 #include "nsWeakReference.h"
 
@@ -304,7 +305,7 @@ gfxPlatform::OptimizeImage(gfxImageSurface *aSurface,
 nsresult
 gfxPlatform::GetFontList(const nsACString& aLangGroup,
                          const nsACString& aGenericFamily,
-                         nsStringArray& aListOfFonts)
+                         nsTArray<nsString>& aListOfFonts)
 {
     return NS_ERROR_NOT_IMPLEMENTED;
 }
diff --git a/gfx/thebes/src/gfxPlatformGtk.cpp b/gfx/thebes/src/gfxPlatformGtk.cpp
index 55b4bdc56d2..3ff86e1524d 100644
--- a/gfx/thebes/src/gfxPlatformGtk.cpp
+++ b/gfx/thebes/src/gfxPlatformGtk.cpp
@@ -248,7 +248,7 @@ gfxPlatformGtk::CreateOffscreenSurface(const gfxIntSize& size,
 nsresult
 gfxPlatformGtk::GetFontList(const nsACString& aLangGroup,
                             const nsACString& aGenericFamily,
-                            nsStringArray& aListOfFonts)
+                            nsTArray<nsString>& aListOfFonts)
 {
     return sFontconfigUtils->GetFontList(aLangGroup, aGenericFamily,
                                          aListOfFonts);
@@ -335,7 +335,7 @@ gfxPlatformGtk::IsFontFormatSupported(nsIURI *aFontURI, PRUint32 aFormatFlags)
 nsresult
 gfxPlatformGtk::GetFontList(const nsACString& aLangGroup,
                             const nsACString& aGenericFamily,
-                            nsStringArray& aListOfFonts)
+                            nsTArray<nsString>& aListOfFonts)
 {
     return sFontconfigUtils->GetFontList(aLangGroup, aGenericFamily,
                                          aListOfFonts);
diff --git a/gfx/thebes/src/gfxPlatformMac.cpp b/gfx/thebes/src/gfxPlatformMac.cpp
index 5a1125e14f6..b320a84c70f 100644
--- a/gfx/thebes/src/gfxPlatformMac.cpp
+++ b/gfx/thebes/src/gfxPlatformMac.cpp
@@ -51,6 +51,7 @@
 #include "nsIPrefLocalizedString.h"
 #include "nsServiceManagerUtils.h"
 #include "nsCRT.h"
+#include "nsTArray.h"
 
 #include "lcms.h"
 
@@ -163,7 +164,7 @@ gfxPlatformMac::IsFontFormatSupported(nsIURI *aFontURI, PRUint32 aFormatFlags)
 nsresult
 gfxPlatformMac::GetFontList(const nsACString& aLangGroup,
                             const nsACString& aGenericFamily,
-                            nsStringArray& aListOfFonts)
+                            nsTArray<nsString>& aListOfFonts)
 {
     gfxQuartzFontCache::SharedFontCache()->
         GetFontList(aLangGroup, aGenericFamily, aListOfFonts);
diff --git a/gfx/thebes/src/gfxQtPlatform.cpp b/gfx/thebes/src/gfxQtPlatform.cpp
index 8a757fd74a4..92677b75221 100644
--- a/gfx/thebes/src/gfxQtPlatform.cpp
+++ b/gfx/thebes/src/gfxQtPlatform.cpp
@@ -57,6 +57,7 @@
 #include <fontconfig/fontconfig.h>
 
 #include "nsMathUtils.h"
+#include "nsTArray.h"
 
 #include "lcms.h"
 
@@ -133,7 +134,7 @@ gfxQtPlatform::CreateOffscreenSurface(const gfxIntSize& size,
 nsresult
 gfxQtPlatform::GetFontList(const nsACString& aLangGroup,
                             const nsACString& aGenericFamily,
-                            nsStringArray& aListOfFonts)
+                            nsTArray<nsString>& aListOfFonts)
 {
     return sFontconfigUtils->GetFontList(aLangGroup, aGenericFamily,
                                          aListOfFonts);
diff --git a/gfx/thebes/src/gfxQuartzFontCache.h b/gfx/thebes/src/gfxQuartzFontCache.h
index 0201a206ffd..fe042e6399f 100644
--- a/gfx/thebes/src/gfxQuartzFontCache.h
+++ b/gfx/thebes/src/gfxQuartzFontCache.h
@@ -51,6 +51,7 @@
 
 #include "nsUnicharUtils.h"
 #include "nsVoidArray.h"
+#include "nsTArray.h"
 
 // used when picking fallback font
 struct FontSearch {
@@ -210,7 +211,7 @@ public:
     
     void GetFontList (const nsACString& aLangGroup,
                       const nsACString& aGenericFamily,
-                      nsStringArray& aListOfFonts);
+                      nsTArray<nsString>& aListOfFonts);
     PRBool ResolveFontName(const nsAString& aFontName,
                            nsAString& aResolvedFontName);
     PRBool GetStandardFamilyName(const nsAString& aFontName, nsAString& aFamilyName);
diff --git a/gfx/thebes/src/gfxQuartzFontCache.mm b/gfx/thebes/src/gfxQuartzFontCache.mm
index df3adeb7c5e..fb12f9ceeec 100644
--- a/gfx/thebes/src/gfxQuartzFontCache.mm
+++ b/gfx/thebes/src/gfxQuartzFontCache.mm
@@ -49,6 +49,7 @@
 
 #include "nsIPref.h"  // for pref changes callback notification
 #include "nsServiceManagerUtils.h"
+#include "nsTArray.h"
 
 #include "nsDirectoryServiceUtils.h"
 #include "nsDirectoryServiceDefs.h"
@@ -1101,12 +1102,12 @@ gfxQuartzFontCache::GetDefaultFont(const gfxFontStyle* aStyle, PRBool& aNeedsBol
 struct FontListData {
     FontListData(const nsACString& aLangGroup,
                  const nsACString& aGenericFamily,
-                 nsStringArray& aListOfFonts) :
+                 nsTArray<nsString>& aListOfFonts) :
         mLangGroup(aLangGroup), mGenericFamily(aGenericFamily),
         mListOfFonts(aListOfFonts) {}
     const nsACString& mLangGroup;
     const nsACString& mGenericFamily;
-    nsStringArray& mListOfFonts;
+    nsTArray<nsString>& mListOfFonts;
 };
 
 PLDHashOperator PR_CALLBACK
@@ -1118,14 +1119,14 @@ gfxQuartzFontCache::HashEnumFuncForFamilies(nsStringHashKey::KeyType aKey,
 
     nsAutoString localizedFamilyName;
     aFamilyEntry->LocalizedName(localizedFamilyName);
-    data->mListOfFonts.AppendString(localizedFamilyName);
+    data->mListOfFonts.AppendElement(localizedFamilyName);
     return PL_DHASH_NEXT;
 }
 
 void
 gfxQuartzFontCache::GetFontList (const nsACString& aLangGroup,
                                  const nsACString& aGenericFamily,
-                                 nsStringArray& aListOfFonts)
+                                 nsTArray<nsString>& aListOfFonts)
 {
     FontListData data(aLangGroup, aGenericFamily, aListOfFonts);
 
diff --git a/gfx/thebes/src/gfxWindowsPlatform.cpp b/gfx/thebes/src/gfxWindowsPlatform.cpp
index 5d69bf3bb6a..4e2441720bb 100644
--- a/gfx/thebes/src/gfxWindowsPlatform.cpp
+++ b/gfx/thebes/src/gfxWindowsPlatform.cpp
@@ -47,6 +47,7 @@
 
 #include "nsIPref.h"
 #include "nsServiceManagerUtils.h"
+#include "nsTArray.h"
 
 #include "nsIWindowsRegKey.h"
 #include "nsILocalFile.h"
@@ -150,11 +151,11 @@ gfxWindowsPlatform::FontEnumProc(const ENUMLOGFONTEXW *lpelfe,
 // general cmap reading routines moved to gfxFontUtils.cpp
 
 struct FontListData {
-    FontListData(const nsACString& aLangGroup, const nsACString& aGenericFamily, nsStringArray& aListOfFonts) :
+    FontListData(const nsACString& aLangGroup, const nsACString& aGenericFamily, nsTArray<nsString>& aListOfFonts) :
         mLangGroup(aLangGroup), mGenericFamily(aGenericFamily), mStringArray(aListOfFonts) {}
     const nsACString& mLangGroup;
     const nsACString& mGenericFamily;
-    nsStringArray& mStringArray;
+    nsTArray<nsString>& mStringArray;
 };
 
 PLDHashOperator
@@ -185,7 +186,7 @@ gfxWindowsPlatform::HashEnumFunc(nsStringHashKey::KeyType aKey,
 nsresult
 gfxWindowsPlatform::GetFontList(const nsACString& aLangGroup,
                                 const nsACString& aGenericFamily,
-                                nsStringArray& aListOfFonts)
+                                nsTArray<nsString>& aListOfFonts)
 {
     FontListData data(aLangGroup, aGenericFamily, aListOfFonts);
 
@@ -270,7 +271,7 @@ gfxWindowsPlatform::UpdateFontList()
         if (!actualFontName.IsEmpty() && mFonts.Get(actualFontName, &ff))
             mFontSubstitutes.Put(substituteName, ff);
         else
-            mNonExistingFonts.AppendString(substituteName);
+            mNonExistingFonts.AppendElement(substituteName);
     }
 
     // initialize ranges of characters for which system-wide font search should be skipped
@@ -374,7 +375,7 @@ gfxWindowsPlatform::ResolveFontName(const nsAString& aFontName,
         return NS_OK;
     }
 
-    if (mNonExistingFonts.IndexOf(keyName) >= 0) {
+    if (mNonExistingFonts.Contains(keyName)) {
         aAborted = PR_FALSE;
         return NS_OK;
     }
@@ -395,7 +396,7 @@ gfxWindowsPlatform::ResolveFontName(const nsAString& aFontName,
                                     (FONTENUMPROCW)gfxWindowsPlatform::FontResolveProc,
                                     (LPARAM)&data, 0);
     if (data.mFoundCount == 0)
-        mNonExistingFonts.AppendString(keyName);
+        mNonExistingFonts.AppendElement(keyName);
     ::ReleaseDC(nsnull, dc);
 
     return NS_OK;
diff --git a/intl/chardet/src/nsMetaCharsetObserver.cpp b/intl/chardet/src/nsMetaCharsetObserver.cpp
index 50da1bd9849..0c876275d97 100644
--- a/intl/chardet/src/nsMetaCharsetObserver.cpp
+++ b/intl/chardet/src/nsMetaCharsetObserver.cpp
@@ -137,8 +137,8 @@ NS_IMETHODIMP nsMetaCharsetObserver::Notify(
                      nsISupports* aWebShell,
                      nsISupports* aChannel,
                      const PRUnichar* aTag, 
-                     const nsStringArray* keys, 
-                     const nsStringArray* values,
+                     const nsTArray<nsString>* keys, 
+                     const nsTArray<nsString>* values,
                      const PRUint32 aFlags)
 {
   nsresult result = NS_OK;
@@ -159,13 +159,13 @@ NS_IMETHODIMP nsMetaCharsetObserver::Notify(
 NS_IMETHODIMP nsMetaCharsetObserver::Notify(
                     nsISupports* aWebShell,
                     nsISupports* aChannel,
-                    const nsStringArray* keys, 
-                    const nsStringArray* values)
+                    const nsTArray<nsString>* keys, 
+                    const nsTArray<nsString>* values)
 {
     NS_PRECONDITION(keys!=nsnull && values!=nsnull,"Need key-value pair");
 
-    PRInt32 numOfAttributes = keys->Count();
-    NS_ASSERTION( numOfAttributes == values->Count(), "size mismatch");
+    PRUint32 numOfAttributes = keys->Length();
+    NS_ASSERTION( numOfAttributes == values->Length(), "size mismatch");
     nsresult res=NS_OK;
 #ifdef DEBUG
 
@@ -174,9 +174,9 @@ NS_IMETHODIMP nsMetaCharsetObserver::Notify(
     PRUnichar Ucharset[]={'c','h','a','r','s','e','t','\0'};
     
     NS_ASSERTION(numOfAttributes >= 3, "should have at least 3 private attribute");
-    NS_ASSERTION(0==nsCRT::strcmp(Uxcommand,(keys->StringAt(numOfAttributes-1))->get()),"last name should be 'X_COMMAND'" );
-    NS_ASSERTION(0==nsCRT::strcmp(UcharsetSource,(keys->StringAt(numOfAttributes-2))->get()),"2nd last name should be 'charsetSource'" );
-    NS_ASSERTION(0==nsCRT::strcmp(Ucharset,(keys->StringAt(numOfAttributes-3))->get()),"3rd last name should be 'charset'" );
+    NS_ASSERTION(0==nsCRT::strcmp(Uxcommand,(keys->ElementAt(numOfAttributes-1)).get()),"last name should be 'X_COMMAND'" );
+    NS_ASSERTION(0==nsCRT::strcmp(UcharsetSource,(keys->ElementAt(numOfAttributes-2)).get()),"2nd last name should be 'charsetSource'" );
+    NS_ASSERTION(0==nsCRT::strcmp(Ucharset,(keys->ElementAt(numOfAttributes-3)).get()),"3rd last name should be 'charset'" );
 
 #endif
     NS_ASSERTION(mAlias, "Didn't get nsICharsetAlias in constructor");
@@ -187,10 +187,8 @@ NS_IMETHODIMP nsMetaCharsetObserver::Notify(
     // we need at least 5 - HTTP-EQUIV, CONTENT and 3 private
     if(numOfAttributes >= 5 ) 
     {
-      const PRUnichar *charset = (values->StringAt(numOfAttributes-3))->get();
-      const PRUnichar *source =  (values->StringAt(numOfAttributes-2))->get();
+      const nsString& srcStr =  values->ElementAt(numOfAttributes-2);
       PRInt32 err;
-      nsAutoString srcStr(source);
       PRInt32  src = srcStr.ToInteger(&err);
       // if we cannot convert the string into PRInt32, return error
       NS_ASSERTION(NS_SUCCEEDED(err), "cannot get charset source");
@@ -200,15 +198,14 @@ NS_IMETHODIMP nsMetaCharsetObserver::Notify(
       if(kCharsetFromMetaTag <= src)
           return NS_OK; // current charset has higher priority. don't bother to do the following
 
-      PRInt32 i;
       const PRUnichar *httpEquivValue=nsnull;
       const PRUnichar *contentValue=nsnull;
       const PRUnichar *charsetValue=nsnull;
 
-      for(i=0;i<(numOfAttributes-3);i++)
+      for (PRUint32 i = 0; i < numOfAttributes - 3; i++)
       {
         const PRUnichar *keyStr;
-        keyStr = (keys->StringAt(i))->get();
+        keyStr = keys->ElementAt(i).get();
 
         //Change 3.190 in nsHTMLTokens.cpp allow  ws/tab/cr/lf exist before 
         // and after text value, this need to be skipped before comparison
@@ -216,11 +213,11 @@ NS_IMETHODIMP nsMetaCharsetObserver::Notify(
           keyStr++;
 
         if(Substring(keyStr, keyStr+10).LowerCaseEqualsLiteral("http-equiv"))
-              httpEquivValue = values->StringAt(i)->get();
+              httpEquivValue = values->ElementAt(i).get();
         else if(Substring(keyStr, keyStr+7).LowerCaseEqualsLiteral("content"))
-              contentValue = values->StringAt(i)->get();
+              contentValue = values->ElementAt(i).get();
         else if (Substring(keyStr, keyStr+7).LowerCaseEqualsLiteral("charset"))
-              charsetValue = values->StringAt(i)->get();
+              charsetValue = values->ElementAt(i).get();
       }
       NS_NAMED_LITERAL_STRING(contenttype, "Content-Type");
       NS_NAMED_LITERAL_STRING(texthtml, "text/html");
@@ -278,7 +275,8 @@ NS_IMETHODIMP nsMetaCharsetObserver::Notify(
              LossyCopyUTF16toASCII(nsDependentString(charsetValue), newCharset);
          } 
 
-         nsCAutoString charsetString; charsetString.AssignWithConversion(charset);
+         nsCAutoString charsetString;
+         charsetString.AssignWithConversion(values->ElementAt(numOfAttributes-3));
          
          if (!newCharset.IsEmpty())
          {    
@@ -333,8 +331,8 @@ NS_IMETHODIMP nsMetaCharsetObserver::Notify(
 
 //-------------------------------------------------------------------------
 NS_IMETHODIMP nsMetaCharsetObserver::GetCharsetFromCompatibilityTag(
-                     const nsStringArray* keys, 
-                     const nsStringArray* values, 
+                     const nsTArray<nsString>* keys, 
+                     const nsTArray<nsString>* values, 
                      nsAString& aCharset)
 {
     if (!mAlias)
@@ -346,11 +344,11 @@ NS_IMETHODIMP nsMetaCharsetObserver::GetCharsetFromCompatibilityTag(
 
     // support for non standard case for compatibility
     // e.g. <META charset="ISO-8859-1">
-    PRInt32 numOfAttributes = keys->Count();
+    PRUint32 numOfAttributes = keys->Length();
     if ((numOfAttributes >= 3) &&
-        (keys->StringAt(0)->LowerCaseEqualsLiteral("charset")))
+        (keys->ElementAt(0).LowerCaseEqualsLiteral("charset")))
     {
-      nsAutoString srcStr((values->StringAt(numOfAttributes-2))->get());
+      const nsString& srcStr = values->ElementAt(numOfAttributes-2);
       PRInt32 err;
       PRInt32  src = srcStr.ToInteger(&err);
       // if we cannot convert the string into PRInt32, return error
@@ -361,7 +359,7 @@ NS_IMETHODIMP nsMetaCharsetObserver::GetCharsetFromCompatibilityTag(
       if (kCharsetFromMetaTag > src)
       {
           nsCAutoString newCharset;
-          newCharset.AssignWithConversion(values->StringAt(0)->get());
+          newCharset.AssignWithConversion(values->ElementAt(0).get());
           
           nsCAutoString preferred;
           res = mAlias->GetPreferred(newCharset,
@@ -371,8 +369,8 @@ NS_IMETHODIMP nsMetaCharsetObserver::GetCharsetFromCompatibilityTag(
               // compare against the current charset, 
               // also some charsets which should have been found in
               // the BOM detection.
-              nsString* currentCharset = values->StringAt(numOfAttributes-3);
-              if (!preferred.Equals(NS_LossyConvertUTF16toASCII(*currentCharset)) &&
+              const nsString& currentCharset = values->ElementAt(numOfAttributes-3);
+              if (!preferred.Equals(NS_LossyConvertUTF16toASCII(currentCharset)) &&
                   !preferred.EqualsLiteral("UTF-16") &&
                   !preferred.EqualsLiteral("UTF-16BE") &&
                   !preferred.EqualsLiteral("UTF-16LE") &&
diff --git a/intl/chardet/src/nsMetaCharsetObserver.h b/intl/chardet/src/nsMetaCharsetObserver.h
index 547e32d6352..db3cc251323 100644
--- a/intl/chardet/src/nsMetaCharsetObserver.h
+++ b/intl/chardet/src/nsMetaCharsetObserver.h
@@ -43,6 +43,7 @@
 #include "nsIObserver.h"
 #include "nsObserverBase.h"
 #include "nsWeakReference.h"
+#include "nsTArray.h"
 
 //========================================================================== 
 //
@@ -76,8 +77,8 @@ public:
   NS_IMETHOD Notify(nsISupports* aWebShell, 
                     nsISupports* aChannel,
                     const PRUnichar* aTag, 
-                    const nsStringArray* keys, 
-                    const nsStringArray* values,
+                    const nsTArray<nsString>* keys, 
+                    const nsTArray<nsString>* values,
                     const PRUint32 aFlags);
 
   NS_DECL_ISUPPORTS
@@ -96,11 +97,11 @@ private:
 
   NS_IMETHOD Notify(nsISupports* aWebShell, 
                     nsISupports* aChannel,
-                    const nsStringArray* keys, 
-                    const nsStringArray* values);
+                    const nsTArray<nsString>* keys, 
+                    const nsTArray<nsString>* values);
 
-  NS_IMETHOD GetCharsetFromCompatibilityTag(const nsStringArray* keys, 
-                                            const nsStringArray* values, 
+  NS_IMETHOD GetCharsetFromCompatibilityTag(const nsTArray<nsString>* keys, 
+                                            const nsTArray<nsString>* values, 
                                             nsAString& aCharset);
 
   nsCOMPtr<nsICharsetAlias> mAlias;
diff --git a/intl/chardet/src/nsXMLEncodingObserver.h b/intl/chardet/src/nsXMLEncodingObserver.h
index b4aa396e7ef..9a8a311a01a 100644
--- a/intl/chardet/src/nsXMLEncodingObserver.h
+++ b/intl/chardet/src/nsXMLEncodingObserver.h
@@ -44,6 +44,7 @@
 #include "nsIObserverService.h"
 #include "nsObserverBase.h"
 #include "nsWeakReference.h"
+#include "nsTArray.h"
 
 class nsXMLEncodingObserver: public nsIElementObserver, 
                              public nsIObserver, 
@@ -71,8 +72,8 @@ public:
   NS_IMETHOD Notify(nsISupports* aWebShell,
                     nsISupports* aChannel,
                     const PRUnichar* aTag, 
-                    const nsStringArray* keys, 
-                    const nsStringArray* values,
+                    const nsTArray<nsString>* keys, 
+                    const nsTArray<nsString>* values,
                     const PRUint32 aFlags)
   { return NS_ERROR_NOT_IMPLEMENTED; }
 
diff --git a/intl/locale/src/nsLocale.cpp b/intl/locale/src/nsLocale.cpp
index 6418d95538c..466c9571c6e 100644
--- a/intl/locale/src/nsLocale.cpp
+++ b/intl/locale/src/nsLocale.cpp
@@ -78,11 +78,10 @@ nsLocale::nsLocale(nsLocale* other) : fHashtable(nsnull), fCategoryCount(0)
 }
 
 
-nsLocale::nsLocale(const nsStringArray& categoryList, 
-                   const nsStringArray& valueList) 
+nsLocale::nsLocale(const nsTArray<nsString>& categoryList, 
+                   const nsTArray<nsString>& valueList) 
                   : fHashtable(NULL), fCategoryCount(0)
 {
-  PRInt32 i;
   PRUnichar* key, *value;
 
   fHashtable = PL_NewHashTable(LOCALE_HASH_SIZE,&nsLocale::Hash_HashFunction,
@@ -93,11 +92,11 @@ nsLocale::nsLocale(const nsStringArray& categoryList,
 
   if (fHashtable)
   {
-    for(i=0; i < categoryList.Count(); ++i) 
+    for(PRUint32 i=0; i < categoryList.Length(); ++i) 
     {
-      key = ToNewUnicode(*categoryList.StringAt(i));
+      key = ToNewUnicode(categoryList[i]);
       NS_ASSERTION(key, "nsLocale: failed to allocate internal hash key");
-      value = ToNewUnicode(*valueList.StringAt(i));
+      value = ToNewUnicode(valueList[i]);
       NS_ASSERTION(value, "nsLocale: failed to allocate internal hash value");
       if (!PL_HashTableAdd(fHashtable,key,value)) {
           nsMemory::Free(key);
diff --git a/intl/locale/src/nsLocale.h b/intl/locale/src/nsLocale.h
index 32619300d75..7a092af557d 100644
--- a/intl/locale/src/nsLocale.h
+++ b/intl/locale/src/nsLocale.h
@@ -53,18 +53,17 @@
 #define nsLocale_h__
 
 #include "nsString.h"
+#include "nsTArray.h"
 #include "nsILocale.h"
 #include "plhash.h"
 
-class nsStringArray;
-
 class nsLocale : public nsILocale {
 	friend class nsLocaleService;
 	NS_DECL_ISUPPORTS
 
 public:
 	nsLocale(void);
-	nsLocale(const nsStringArray& categoryList, const nsStringArray& valueList);
+	nsLocale(const nsTArray<nsString>& categoryList, const nsTArray<nsString>& valueList);
 	nsLocale(nsLocale* other);
 	virtual ~nsLocale(void);
 	
diff --git a/layout/base/nsIPresShell.h b/layout/base/nsIPresShell.h
index e925f356f46..e58e0dc2fe5 100644
--- a/layout/base/nsIPresShell.h
+++ b/layout/base/nsIPresShell.h
@@ -79,7 +79,6 @@ class nsIRenderingContext;
 class nsIPageSequenceFrame;
 class nsString;
 class nsAString;
-class nsStringArray;
 class nsCaret;
 class nsStyleContext;
 class nsFrameSelection;
diff --git a/layout/mathml/base/src/nsMathMLChar.cpp b/layout/mathml/base/src/nsMathMLChar.cpp
index 6babe541bc9..aa9a029b86c 100644
--- a/layout/mathml/base/src/nsMathMLChar.cpp
+++ b/layout/mathml/base/src/nsMathMLChar.cpp
@@ -220,7 +220,7 @@ public:
       mCharCache(0)
   {
     MOZ_COUNT_CTOR(nsGlyphTable);
-    mFontName.AppendString(aPrimaryFontName);
+    mFontName.AppendElement(aPrimaryFontName);
   }
 
   ~nsGlyphTable() // not a virtual destructor: this class is not intended to be subclassed
@@ -230,12 +230,12 @@ public:
 
   const nsAString& PrimaryFontName() const
   {
-    return *mFontName.StringAt(0);
+    return mFontName[0];
   }
 
   const nsAString& FontNameFor(const nsGlyphCode& aGlyphCode) const
   {
-    return *mFontName.StringAt(aGlyphCode.font);
+    return mFontName[aGlyphCode.font];
   }
 
   // True if this table contains some glyphs (variants and/or parts)
@@ -286,7 +286,7 @@ private:
   // mFontName[0] is the primary font associated to this table. The others 
   // are possible "external" fonts for glyphs not in the primary font
   // but which are needed to stretch certain characters in the table
-  nsStringArray mFontName; 
+  nsTArray<nsString> mFontName; 
                                
   // Tri-state variable for error/empty/ready
   PRInt32 mState;
@@ -320,11 +320,11 @@ nsGlyphTable::ElementAt(nsPresContext* aPresContext, nsMathMLChar* aChar, PRUint
   if (mState == NS_TABLE_STATE_ERROR) return kNullGlyph;
   // Load glyph properties if this is the first time we have been here
   if (mState == NS_TABLE_STATE_EMPTY) {
-    nsresult rv = LoadProperties(*mFontName[0], mGlyphProperties);
+    nsresult rv = LoadProperties(mFontName[0], mGlyphProperties);
 #ifdef NS_DEBUG
     nsCAutoString uriStr;
     uriStr.AssignLiteral("resource://gre/res/fonts/mathfont");
-    LossyAppendUTF16toASCII(*mFontName[0], uriStr);
+    LossyAppendUTF16toASCII(mFontName[0], uriStr);
     uriStr.StripWhitespace(); // that may come from mFontName
     uriStr.AppendLiteral(".properties");
     printf("Loading %s ... %s\n",
@@ -346,7 +346,7 @@ nsGlyphTable::ElementAt(nsPresContext* aPresContext, nsMathMLChar* aChar, PRUint
       rv = mGlyphProperties->GetStringProperty(key, value);
       if (NS_FAILED(rv)) break;
       Clean(value);
-      mFontName.AppendString(value); // i.e., mFontName[i] holds this font name
+      mFontName.AppendElement(value); // i.e., mFontName[i] holds this font name
     }
   }
 
@@ -410,14 +410,12 @@ nsGlyphTable::ElementAt(nsPresContext* aPresContext, nsMathMLChar* aChar, PRUint
         ++i;
         font = value[i] - '0';
         ++i;
-        if (font >= mFontName.Count()) {
+        if (font >= mFontName.Length()) {
           NS_ERROR("Non-existant font referenced in glyph table");
           return kNullGlyph;
         }
         // The char cannot be handled if this font is not installed
-        nsAutoString fontName;
-        mFontName.StringAt(font, fontName);
-        if (!fontName.Length() || !CheckFontExistence(aPresContext, fontName)) {
+        if (!mFontName[font].Length() || !CheckFontExistence(aPresContext, mFontName[font])) {
           return kNullGlyph;
         }
       }
@@ -1568,7 +1566,6 @@ nsMathMLChar::StretchInternal(nsPresContext*           aPresContext,
   // Set default font and get the default bounding metrics
   // mStyleContext is a leaf context used only when stretching happens.
   // For the base size, the default font should come from the parent context
-  nsAutoString fontName;
   nsFont font = mStyleContext->GetParent()->GetStyleFont()->mFont;
 
   // Override with specific fonts if applicable for this character
@@ -2092,7 +2089,6 @@ nsMathMLChar::PaintForeground(nsPresContext* aPresContext,
   }
   aRenderingContext.SetColor(fgColor);
 
-  nsAutoString fontName;
   nsFont theFont(styleContext->GetStyleFont()->mFont);
   if (! mFamily.IsEmpty()) {
     theFont.name = mFamily;
diff --git a/layout/mathml/content/src/nsMathMLOperators.cpp b/layout/mathml/content/src/nsMathMLOperators.cpp
index 3ffdb8beaf7..6c973168af6 100644
--- a/layout/mathml/content/src/nsMathMLOperators.cpp
+++ b/layout/mathml/content/src/nsMathMLOperators.cpp
@@ -41,6 +41,7 @@
 #include "nsString.h"
 #include "nsHashtable.h"
 #include "nsVoidArray.h"
+#include "nsTArray.h"
 
 #include "nsIComponentManager.h"
 #include "nsIPersistentProperties2.h"
@@ -81,7 +82,7 @@ static PRInt32         gOperatorCount = 0;
 static OperatorData*   gOperatorArray = nsnull;
 static nsHashtable*    gOperatorTable = nsnull;
 static nsVoidArray*    gStretchyOperatorArray = nsnull;
-static nsStringArray*  gInvariantCharArray = nsnull;
+static nsTArray<nsString>*  gInvariantCharArray = nsnull;
 static PRBool          gInitialized   = PR_FALSE;
 
 static const PRUnichar kNullCh  = PRUnichar('\0');
@@ -307,7 +308,7 @@ InitOperators(void)
     key.Append(kMathVariant_name[i]);
     nsAutoString value;
     mathfontProp->GetStringProperty(key, value);
-    gInvariantCharArray->AppendString(value); // i.e., gInvariantCharArray[i] holds this list
+    gInvariantCharArray->AppendElement(value); // i.e., gInvariantCharArray[i] holds this list
   }
 
   // Parse the Operator Dictionary in two passes.
@@ -376,7 +377,7 @@ InitGlobals()
 {
   gInitialized = PR_TRUE;
   nsresult rv = NS_ERROR_OUT_OF_MEMORY;
-  gInvariantCharArray = new nsStringArray();
+  gInvariantCharArray = new nsTArray<nsString>();
   gStretchyOperatorArray = new nsVoidArray();
   if (gInvariantCharArray && gStretchyOperatorArray) {
     gOperatorTable = new nsHashtable();
@@ -620,11 +621,11 @@ nsMathMLOperators::LookupInvariantChar(const nsAString& aChar)
     InitGlobals();
   }
   if (gInvariantCharArray) {
-    for (PRInt32 i = gInvariantCharArray->Count()-1; i >= 0; --i) {
-      nsString* list = gInvariantCharArray->StringAt(i);
+    for (PRUint32 i = gInvariantCharArray->Length()-1; i >= 0; --i) {
+      const nsString& list = gInvariantCharArray->ElementAt(i);
       nsString::const_iterator start, end;
-      list->BeginReading(start);
-      list->EndReading(end);
+      list.BeginReading(start);
+      list.EndReading(end);
       // Style-invariant characters are at offset 3*j + 1.
       if (FindInReadable(aChar, start, end) &&
           start.size_backward() % 3 == 1) {
@@ -643,15 +644,15 @@ nsMathMLOperators::TransformVariantChar(const PRUnichar& aChar,
     InitGlobals();
   }
   if (gInvariantCharArray) {
-    nsString* list = gInvariantCharArray->StringAt(aVariant);
-    PRInt32 index = list->FindChar(aChar);
+    nsString list = gInvariantCharArray->ElementAt(aVariant);
+    PRInt32 index = list.FindChar(aChar);
     // BMP characters are at offset 3*j
-    if (index != kNotFound && index % 3 == 0 && list->Length() - index >= 2 ) {
+    if (index != kNotFound && index % 3 == 0 && list.Length() - index >= 2 ) {
       // The style-invariant character is the next character
       // (and list should contain padding if the next character is in the BMP).
       ++index;
-      PRUint32 len = NS_IS_HIGH_SURROGATE(list->CharAt(index)) ? 2 : 1;
-      return nsDependentSubstring(*list, index, len);
+      PRUint32 len = NS_IS_HIGH_SURROGATE(list.CharAt(index)) ? 2 : 1;
+      return nsDependentSubstring(list, index, len);
     }
   }
   return nsDependentSubstring(&aChar, &aChar + 1);  
diff --git a/parser/htmlparser/public/nsIElementObserver.h b/parser/htmlparser/public/nsIElementObserver.h
index 3a463876be0..3cf72b24d63 100644
--- a/parser/htmlparser/public/nsIElementObserver.h
+++ b/parser/htmlparser/public/nsIElementObserver.h
@@ -49,6 +49,7 @@
 #include "prtypes.h"
 #include "nsHTMLTags.h"
 #include "nsVoidArray.h"
+#include "nsTArray.h"
 
 
 // {4672AA04-F6AE-11d2-B3B7-00805F8A6670}
@@ -80,8 +81,8 @@ public:
   NS_IMETHOD Notify(nsISupports* aWebShell, 
                     nsISupports* aChannel,
                     const PRUnichar* aTag, 
-                    const nsStringArray* aKeys, 
-                    const nsStringArray* aValues,
+                    const nsTArray<nsString>* aKeys, 
+                    const nsTArray<nsString>* aValues,
                     const PRUint32 aFlags) = 0;
 
 };
diff --git a/parser/htmlparser/src/CNavDTD.cpp b/parser/htmlparser/src/CNavDTD.cpp
index 1874f361f13..1b87752e5a5 100644
--- a/parser/htmlparser/src/CNavDTD.cpp
+++ b/parser/htmlparser/src/CNavDTD.cpp
@@ -57,6 +57,7 @@
 #include "nsLinebreakConverter.h"
 #include "nsIFormProcessor.h"
 #include "nsVoidArray.h"
+#include "nsTArray.h"
 #include "nsReadableUtils.h"
 #include "nsUnicharUtils.h"
 #include "prmem.h"
@@ -1230,7 +1231,7 @@ CNavDTD::HandleKeyGen(nsIParserNode* aNode)
   }
 
   PRInt32      theAttrCount = aNode->GetAttributeCount();
-  nsStringArray  theContent;
+  nsTArray<nsString> theContent;
   nsAutoString theAttribute;
   nsAutoString theFormType;
   CToken*      theToken = nsnull;
@@ -1242,7 +1243,6 @@ CNavDTD::HandleKeyGen(nsIParserNode* aNode)
   if (NS_FAILED(result)) {
     return result;
   }
-  nsString* theTextValue = nsnull;
   PRInt32   theIndex = nsnull;
 
   // Populate the tokenizer with the fabricated elements in the reverse
@@ -1253,11 +1253,10 @@ CNavDTD::HandleKeyGen(nsIParserNode* aNode)
   NS_ENSURE_TRUE(theToken, NS_ERROR_OUT_OF_MEMORY);
   mTokenizer->PushTokenFront(theToken);
 
-  for (theIndex = theContent.Count()-1; theIndex > -1; --theIndex) {
-    theTextValue = theContent[theIndex];
+  for (theIndex = theContent.Length()-1; theIndex > -1; --theIndex) {
     theToken = mTokenAllocator->CreateTokenOfType(eToken_text,
                                                   eHTMLTag_text,
-                                                  *theTextValue);
+                                                  theContent[theIndex]);
     NS_ENSURE_TRUE(theToken, NS_ERROR_OUT_OF_MEMORY);
     mTokenizer->PushTokenFront(theToken);
 
diff --git a/parser/htmlparser/src/nsDTDUtils.cpp b/parser/htmlparser/src/nsDTDUtils.cpp
index 2f4ce50dc1e..056157b83dc 100644
--- a/parser/htmlparser/src/nsDTDUtils.cpp
+++ b/parser/htmlparser/src/nsDTDUtils.cpp
@@ -1075,7 +1075,7 @@ nsObserverEntry::Notify(nsIParserNode* aNode,
       PRInt32 theAttrCount = aNode->GetAttributeCount(); 
       PRInt32 theObserversCount = theObservers->Count(); 
       if (0 < theObserversCount){
-        nsStringArray keys(theAttrCount+4), values(theAttrCount+4);
+        nsTArray<nsString> keys(theAttrCount + 4), values(theAttrCount + 4);
 
         // XXX this and the following code may be a performance issue.
         // Every key and value is copied and added to an voidarray (causing at
@@ -1083,21 +1083,21 @@ nsObserverEntry::Notify(nsIParserNode* aNode,
         // string (total = 2*(keys+3) + 2(or more) array allocations )).
         PRInt32 index;
         for (index = 0; index < theAttrCount; ++index) {
-          keys.AppendString(aNode->GetKeyAt(index));
-          values.AppendString(aNode->GetValueAt(index));
+          keys.AppendElement(aNode->GetKeyAt(index));
+          values.AppendElement(aNode->GetValueAt(index));
         } 
 
         nsAutoString intValue;
 
-        keys.AppendString(NS_LITERAL_STRING("charset")); 
-        values.AppendString(theCharsetValue);       
+        keys.AppendElement(NS_LITERAL_STRING("charset")); 
+        values.AppendElement(theCharsetValue);       
       
-        keys.AppendString(NS_LITERAL_STRING("charsetSource")); 
+        keys.AppendElement(NS_LITERAL_STRING("charsetSource")); 
         intValue.AppendInt(PRInt32(theCharsetSource),10);
-        values.AppendString(intValue); 
+        values.AppendElement(intValue); 
 
-        keys.AppendString(NS_LITERAL_STRING("X_COMMAND"));
-        values.AppendString(NS_LITERAL_STRING("text/html")); 
+        keys.AppendElement(NS_LITERAL_STRING("X_COMMAND"));
+        values.AppendElement(NS_LITERAL_STRING("text/html")); 
 
         nsCOMPtr<nsIChannel> channel;
         aParser->GetChannel(getter_AddRefs(channel));
diff --git a/security/manager/ssl/src/nsKeygenHandler.cpp b/security/manager/ssl/src/nsKeygenHandler.cpp
index 384524b4675..f389c3fddba 100644
--- a/security/manager/ssl/src/nsKeygenHandler.cpp
+++ b/security/manager/ssl/src/nsKeygenHandler.cpp
@@ -843,14 +843,14 @@ nsKeygenFormProcessor::ProcessValue(nsIDOMHTMLElement *aElement,
 } 
 
 NS_METHOD nsKeygenFormProcessor::ProvideContent(const nsAString& aFormType, 
-						nsStringArray& aContent, 
+						nsTArray<nsString>& aContent, 
 						nsAString& aAttribute) 
 { 
   if (Compare(aFormType, NS_LITERAL_STRING("SELECT"), 
     nsCaseInsensitiveStringComparator()) == 0) {
 
     for (size_t i = 0; i < number_of_key_size_choices; ++i) {
-      aContent.AppendString(mSECKeySizeChoiceList[i].name);
+      aContent.AppendElement(mSECKeySizeChoiceList[i].name);
     }
     aAttribute.AssignLiteral("-mozilla-keygen");
   }
diff --git a/security/manager/ssl/src/nsKeygenHandler.h b/security/manager/ssl/src/nsKeygenHandler.h
index 006d0fe21e3..3a2368dc249 100644
--- a/security/manager/ssl/src/nsKeygenHandler.h
+++ b/security/manager/ssl/src/nsKeygenHandler.h
@@ -41,6 +41,8 @@
 #define _NSKEYGENHANDLER_H_
 // Form Processor 
 #include "nsIFormProcessor.h" 
+#include "nsVoidArray.h" 
+#include "nsTArray.h" 
 
 nsresult GetSlotWithMechanism(PRUint32 mechanism,
                               nsIInterfaceRequestor *ctx,
@@ -62,7 +64,7 @@ public:
                           nsAString& aValue); 
 
   NS_IMETHOD ProvideContent(const nsAString& aFormType, 
-                            nsStringArray& aContent, 
+                            nsTArray<nsString>& aContent, 
                             nsAString& aAttribute); 
   NS_DECL_ISUPPORTS 
 
diff --git a/storage/src/mozStorageStatementWrapper.cpp b/storage/src/mozStorageStatementWrapper.cpp
index 30b5a14ecce..06fe08f370a 100644
--- a/storage/src/mozStorageStatementWrapper.cpp
+++ b/storage/src/mozStorageStatementWrapper.cpp
@@ -80,7 +80,7 @@ mozStorageStatementWrapper::Initialize(mozIStorageStatement *aStatement)
 
     for (unsigned int i = 0; i < mResultColumnCount; i++) {
         const void *name = sqlite3_column_name16 (NativeStatement(), i);
-        mColumnNames.AppendString(nsDependentString(static_cast<const PRUnichar*>(name)));
+        mColumnNames.AppendElement(nsDependentString(static_cast<const PRUnichar*>(name)));
     }
 
     return NS_OK;
diff --git a/storage/src/mozStorageStatementWrapper.h b/storage/src/mozStorageStatementWrapper.h
index f3dd84fe825..71839737e25 100644
--- a/storage/src/mozStorageStatementWrapper.h
+++ b/storage/src/mozStorageStatementWrapper.h
@@ -44,6 +44,7 @@
 #include "nsIXPCScriptable.h"
 
 #include "nsVoidArray.h"
+#include "nsTArray.h"
 
 #include "sqlite3.h"
 
@@ -74,7 +75,7 @@ protected:
     nsRefPtr<mozStorageStatement> mStatement;
     PRUint32 mParamCount;
     PRUint32 mResultColumnCount;
-    nsStringArray mColumnNames;
+    nsTArray<nsString> mColumnNames;
 
     nsCOMPtr<mozIStorageStatementRow> mStatementRow;
     nsCOMPtr<mozIStorageStatementParams> mStatementParams;
diff --git a/toolkit/components/autocomplete/src/nsAutoCompleteSimpleResult.cpp b/toolkit/components/autocomplete/src/nsAutoCompleteSimpleResult.cpp
index 732aa760340..03d08db46a8 100644
--- a/toolkit/components/autocomplete/src/nsAutoCompleteSimpleResult.cpp
+++ b/toolkit/components/autocomplete/src/nsAutoCompleteSimpleResult.cpp
@@ -110,25 +110,23 @@ nsAutoCompleteSimpleResult::AppendMatch(const nsAString& aValue,
                                         const nsAString& aImage,
                                         const nsAString& aStyle)
 {
-  NS_ASSERTION(mValues.Count() == mComments.Count(), "Arrays out of sync");
-  NS_ASSERTION(mValues.Count() == mImages.Count(),   "Arrays out of sync");
-  NS_ASSERTION(mValues.Count() == mStyles.Count(),   "Arrays out of sync");
+  CheckInvariants();
 
-  if (! mValues.AppendString(aValue))
+  if (! mValues.AppendElement(aValue))
     return NS_ERROR_OUT_OF_MEMORY;
-  if (! mComments.AppendString(aComment)) {
-    mValues.RemoveStringAt(mValues.Count() - 1);
+  if (! mComments.AppendElement(aComment)) {
+    mValues.RemoveElementAt(mValues.Length() - 1);
     return NS_ERROR_OUT_OF_MEMORY;
   }
-  if (! mImages.AppendString(aImage)) {
-    mValues.RemoveStringAt(mValues.Count() - 1);
-    mComments.RemoveStringAt(mComments.Count() - 1);
+  if (! mImages.AppendElement(aImage)) {
+    mValues.RemoveElementAt(mValues.Length() - 1);
+    mComments.RemoveElementAt(mComments.Length() - 1);
     return NS_ERROR_OUT_OF_MEMORY;
   }
-  if (! mStyles.AppendString(aStyle)) {
-    mValues.RemoveStringAt(mValues.Count() - 1);
-    mComments.RemoveStringAt(mComments.Count() - 1);
-    mImages.RemoveStringAt(mImages.Count() - 1);
+  if (! mStyles.AppendElement(aStyle)) {
+    mValues.RemoveElementAt(mValues.Length() - 1);
+    mComments.RemoveElementAt(mComments.Length() - 1);
+    mImages.RemoveElementAt(mImages.Length() - 1);
     return NS_ERROR_OUT_OF_MEMORY;
   }
   return NS_OK;
@@ -137,59 +135,50 @@ nsAutoCompleteSimpleResult::AppendMatch(const nsAString& aValue,
 NS_IMETHODIMP
 nsAutoCompleteSimpleResult::GetMatchCount(PRUint32 *aMatchCount)
 {
-  NS_ASSERTION(mValues.Count() == mComments.Count(), "Arrays out of sync");
-  NS_ASSERTION(mValues.Count() == mImages.Count(),   "Arrays out of sync");
-  NS_ASSERTION(mValues.Count() == mStyles.Count(),   "Arrays out of sync");
+  CheckInvariants();
 
-  *aMatchCount = mValues.Count();
+  *aMatchCount = mValues.Length();
   return NS_OK;
 }
 
 NS_IMETHODIMP
 nsAutoCompleteSimpleResult::GetValueAt(PRInt32 aIndex, nsAString& _retval)
 {
-  NS_ENSURE_TRUE(aIndex >= 0 && aIndex < mValues.Count(),
+  NS_ENSURE_TRUE(aIndex >= 0 && aIndex < PRInt32(mValues.Length()),
                  NS_ERROR_ILLEGAL_VALUE);
-  NS_ASSERTION(mValues.Count() == mComments.Count(), "Arrays out of sync");
-  NS_ASSERTION(mValues.Count() == mImages.Count(),   "Arrays out of sync");
-  NS_ASSERTION(mValues.Count() == mStyles.Count(),   "Arrays out of sync");
-  mValues.StringAt(aIndex, _retval);
+  CheckInvariants();
+
+  _retval = mValues[aIndex];
   return NS_OK;
 }
 
 NS_IMETHODIMP
 nsAutoCompleteSimpleResult::GetCommentAt(PRInt32 aIndex, nsAString& _retval)
 {
-  NS_ENSURE_TRUE(aIndex >= 0 && aIndex < mComments.Count(),
+  NS_ENSURE_TRUE(aIndex >= 0 && aIndex < PRInt32(mComments.Length()),
                  NS_ERROR_ILLEGAL_VALUE);
-  NS_ASSERTION(mValues.Count() == mComments.Count(), "Arrays out of sync");
-  NS_ASSERTION(mValues.Count() == mImages.Count(),   "Arrays out of sync");
-  NS_ASSERTION(mValues.Count() == mStyles.Count(),   "Arrays out of sync");
-  mComments.StringAt(aIndex, _retval);
+  CheckInvariants();
+  _retval = mComments[aIndex];
   return NS_OK;
 }
 
 NS_IMETHODIMP
 nsAutoCompleteSimpleResult::GetImageAt(PRInt32 aIndex, nsAString& _retval)
 {
-  NS_ENSURE_TRUE(aIndex >= 0 && aIndex < mImages.Count(),
+  NS_ENSURE_TRUE(aIndex >= 0 && aIndex < PRInt32(mImages.Length()),
                  NS_ERROR_ILLEGAL_VALUE);
-  NS_ASSERTION(mValues.Count() == mComments.Count(), "Arrays out of sync");
-  NS_ASSERTION(mValues.Count() == mImages.Count(),   "Arrays out of sync");
-  NS_ASSERTION(mValues.Count() == mStyles.Count(),   "Arrays out of sync");
-  mImages.StringAt(aIndex, _retval);
+  CheckInvariants();
+  _retval = mImages[aIndex];
   return NS_OK;
 }
 
 NS_IMETHODIMP
 nsAutoCompleteSimpleResult::GetStyleAt(PRInt32 aIndex, nsAString& _retval)
 {
-  NS_ENSURE_TRUE(aIndex >= 0 && aIndex < mStyles.Count(),
+  NS_ENSURE_TRUE(aIndex >= 0 && aIndex < PRInt32(mStyles.Length()),
                  NS_ERROR_ILLEGAL_VALUE);
-  NS_ASSERTION(mValues.Count() == mComments.Count(), "Arrays out of sync");
-  NS_ASSERTION(mValues.Count() == mImages.Count(),   "Arrays out of sync");
-  NS_ASSERTION(mValues.Count() == mStyles.Count(),   "Arrays out of sync");
-  mStyles.StringAt(aIndex, _retval);
+  CheckInvariants();
+  _retval = mStyles[aIndex];
   return NS_OK;
 }
 
@@ -204,14 +193,14 @@ NS_IMETHODIMP
 nsAutoCompleteSimpleResult::RemoveValueAt(PRInt32 aRowIndex,
                                           PRBool aRemoveFromDb)
 {
-  NS_ENSURE_TRUE(aRowIndex >= 0 && aRowIndex < mValues.Count(),
+  NS_ENSURE_TRUE(aRowIndex >= 0 && aRowIndex < PRInt32(mValues.Length()),
                  NS_ERROR_ILLEGAL_VALUE);
 
-  nsAutoString removedValue(*mValues.StringAt(aRowIndex));
-  mValues.RemoveStringAt(aRowIndex);
-  mComments.RemoveStringAt(aRowIndex);
-  mImages.RemoveStringAt(aRowIndex);
-  mStyles.RemoveStringAt(aRowIndex);
+  nsAutoString removedValue(mValues[aRowIndex]);
+  mValues.RemoveElementAt(aRowIndex);
+  mComments.RemoveElementAt(aRowIndex);
+  mImages.RemoveElementAt(aRowIndex);
+  mStyles.RemoveElementAt(aRowIndex);
 
   if (mListener)
     mListener->OnValueRemoved(this, removedValue, aRemoveFromDb);
diff --git a/toolkit/components/autocomplete/src/nsAutoCompleteSimpleResult.h b/toolkit/components/autocomplete/src/nsAutoCompleteSimpleResult.h
index dbdc8ed1beb..95b485055c7 100644
--- a/toolkit/components/autocomplete/src/nsAutoCompleteSimpleResult.h
+++ b/toolkit/components/autocomplete/src/nsAutoCompleteSimpleResult.h
@@ -45,11 +45,17 @@
 #include "nsString.h"
 #include "prtypes.h"
 #include "nsCOMPtr.h"
+#include "nsTArray.h"
 
 class nsAutoCompleteSimpleResult : public nsIAutoCompleteSimpleResult
 {
 public:
   nsAutoCompleteSimpleResult();
+  inline void CheckInvariants() {
+    NS_ASSERTION(mValues.Length() == mComments.Length(), "Arrays out of sync");
+    NS_ASSERTION(mValues.Length() == mImages.Length(),   "Arrays out of sync");
+    NS_ASSERTION(mValues.Length() == mStyles.Length(),   "Arrays out of sync");
+  }
 
   NS_DECL_ISUPPORTS
   NS_DECL_NSIAUTOCOMPLETERESULT
@@ -63,10 +69,10 @@ protected:
   // What we really want is an array of structs with value/comment/image/style contents.
   // But then we'd either have to use COM or manage object lifetimes ourselves.
   // Having four arrays of string simplifies this, but is stupid.
-  nsStringArray mValues;
-  nsStringArray mComments;
-  nsStringArray mImages;
-  nsStringArray mStyles;
+  nsTArray<nsString> mValues;
+  nsTArray<nsString> mComments;
+  nsTArray<nsString> mImages;
+  nsTArray<nsString> mStyles;
 
   nsString mSearchString;
   nsString mErrorDescription;
diff --git a/toolkit/components/commandlines/src/nsCommandLine.cpp b/toolkit/components/commandlines/src/nsCommandLine.cpp
index c4b79330150..42833192a68 100644
--- a/toolkit/components/commandlines/src/nsCommandLine.cpp
+++ b/toolkit/components/commandlines/src/nsCommandLine.cpp
@@ -53,6 +53,7 @@
 #include "nsNetUtil.h"
 #include "nsUnicharUtils.h"
 #include "nsVoidArray.h"
+#include "nsTArray.h"
 #include "nsXPCOMCID.h"
 #include "plstr.h"
 
@@ -99,11 +100,11 @@ protected:
   nsresult EnumerateHandlers(EnumerateHandlersCallback aCallback, void *aClosure);
   nsresult EnumerateValidators(EnumerateValidatorsCallback aCallback, void *aClosure);
 
-  nsStringArray     mArgs;
-  PRUint32          mState;
-  nsCOMPtr<nsIFile> mWorkingDir;
-  nsCOMPtr<nsIDOMWindow> mWindowContext;
-  PRBool            mPreventDefault;
+  nsTArray<nsString>      mArgs;
+  PRUint32                mState;
+  nsCOMPtr<nsIFile>       mWorkingDir;
+  nsCOMPtr<nsIDOMWindow>  mWindowContext;
+  PRBool                  mPreventDefault;
 };
 
 nsCommandLine::nsCommandLine() :
@@ -121,7 +122,7 @@ NS_IMPL_ISUPPORTS2_CI(nsCommandLine,
 NS_IMETHODIMP
 nsCommandLine::GetLength(PRInt32 *aResult)
 {
-  *aResult = mArgs.Count();
+  *aResult = PRInt32(mArgs.Length());
   return NS_OK;
 }
 
@@ -129,9 +130,9 @@ NS_IMETHODIMP
 nsCommandLine::GetArgument(PRInt32 aIndex, nsAString& aResult)
 {
   NS_ENSURE_ARG_MIN(aIndex, 0);
-  NS_ENSURE_ARG_MAX(aIndex, mArgs.Count());
+  NS_ENSURE_ARG_MAX(aIndex, mArgs.Length());
 
-  mArgs.StringAt(aIndex, aResult);
+  aResult = mArgs[aIndex];
   return NS_OK;
 }
 
@@ -140,16 +141,14 @@ nsCommandLine::FindFlag(const nsAString& aFlag, PRBool aCaseSensitive, PRInt32 *
 {
   NS_ENSURE_ARG(!aFlag.IsEmpty());
 
-  PRInt32 f;
-
   nsDefaultStringComparator caseCmp;
   nsCaseInsensitiveStringComparator caseICmp;
   nsStringComparator& c = aCaseSensitive ?
     static_cast<nsStringComparator&>(caseCmp) :
     static_cast<nsStringComparator&>(caseICmp);
 
-  for (f = 0; f < mArgs.Count(); ++f) {
-    const nsString &arg = *mArgs[f];
+  for (PRUint32 f = 0; f < mArgs.Length(); f++) {
+    const nsString &arg = mArgs[f];
 
     if (arg.Length() >= 2 && arg.First() == PRUnichar('-')) {
       if (aFlag.Equals(Substring(arg, 1), c)) {
@@ -167,10 +166,10 @@ NS_IMETHODIMP
 nsCommandLine::RemoveArguments(PRInt32 aStart, PRInt32 aEnd)
 {
   NS_ENSURE_ARG_MIN(aStart, 0);
-  NS_ENSURE_ARG_MAX(aEnd, mArgs.Count() - 1);
+  NS_ENSURE_ARG_MAX(aEnd, mArgs.Length() - 1);
 
   for (PRInt32 i = aEnd; i >= aStart; --i) {
-    mArgs.RemoveStringAt(i);
+    mArgs.RemoveElementAt(i);
   }
 
   return NS_OK;
@@ -212,17 +211,17 @@ nsCommandLine::HandleFlagWithParam(const nsAString& aFlag, PRBool aCaseSensitive
     return NS_OK;
   }
 
-  if (found == mArgs.Count() - 1) {
+  if (found == PRInt32(mArgs.Length()) - 1) {
     return NS_ERROR_INVALID_ARG;
   }
 
   ++found;
 
-  if (mArgs[found]->First() == '-') {
+  if (mArgs[found].First() == '-') {
     return NS_ERROR_INVALID_ARG;
   }
 
-  mArgs.StringAt(found, aResult);
+  aResult = mArgs[found];
   RemoveArguments(found - 1, found);
 
   return NS_OK;
@@ -485,7 +484,7 @@ nsCommandLine::appendArg(const char* arg)
   NS_CopyNativeToUnicode(nsDependentCString(arg), warg);
 #endif
 
-  mArgs.AppendString(warg);
+  mArgs.AppendElement(warg);
 }
 
 void
diff --git a/toolkit/components/filepicker/src/nsFileView.cpp b/toolkit/components/filepicker/src/nsFileView.cpp
index 4f20f8db9dc..cec76bba58a 100644
--- a/toolkit/components/filepicker/src/nsFileView.cpp
+++ b/toolkit/components/filepicker/src/nsFileView.cpp
@@ -58,6 +58,7 @@
 #include "nsISimpleEnumerator.h"
 #include "nsAutoPtr.h"
 #include "nsIMutableArray.h"
+#include "nsTArray.h"
 
 #include "nsWildCard.h"
 
@@ -75,7 +76,7 @@ public:
   NS_DECL_ISUPPORTS
   NS_DECL_NSIAUTOCOMPLETERESULT
 
-  nsStringArray mValues;
+  nsTArray<nsString> mValues;
   nsAutoString mSearchString;
   PRUint16 mSearchResult;
 };
@@ -115,7 +116,7 @@ nsFileResult::nsFileResult(const nsAString& aSearchString,
       nextFile->GetLeafName(fileName);
       if (StringBeginsWith(fileName, prefix)) {
         fileName.Insert(parent, 0);
-        mValues.AppendString(fileName);
+        mValues.AppendElement(fileName);
         if (mSearchResult == RESULT_NOMATCH && fileName.Equals(mSearchString))
           mSearchResult = RESULT_IGNORED;
         else
@@ -155,13 +156,13 @@ NS_IMETHODIMP nsFileResult::GetErrorDescription(nsAString & aErrorDescription)
 NS_IMETHODIMP nsFileResult::GetMatchCount(PRUint32 *aMatchCount)
 {
   NS_ENSURE_ARG_POINTER(aMatchCount);
-  *aMatchCount = mValues.Count();
+  *aMatchCount = mValues.Length();
   return NS_OK;
 }
 
 NS_IMETHODIMP nsFileResult::GetValueAt(PRInt32 index, nsAString & aValue)
 {
-  mValues.StringAt(index, aValue);
+  aValue = mValues[index];
   return NS_OK;
 }
 
diff --git a/toolkit/components/places/src/nsNavHistory.cpp b/toolkit/components/places/src/nsNavHistory.cpp
index de6bdcc5478..32e76754632 100644
--- a/toolkit/components/places/src/nsNavHistory.cpp
+++ b/toolkit/components/places/src/nsNavHistory.cpp
@@ -49,6 +49,7 @@
 #include "nsPlacesTables.h"
 
 #include "nsIArray.h"
+#include "nsTArray.h"
 #include "nsArrayEnumerator.h"
 #include "nsCollationCID.h"
 #include "nsCOMPtr.h"
@@ -248,7 +249,7 @@ static PRInt64 GetSimpleBookmarksQueryFolder(
     const nsCOMArray<nsNavHistoryQuery>& aQueries,
     nsNavHistoryQueryOptions* aOptions);
 static void ParseSearchTermsFromQueries(const nsCOMArray<nsNavHistoryQuery>& aQueries,
-                                        nsTArray<nsStringArray*>* aTerms);
+                                        nsTArray<nsTArray<nsString>*>* aTerms);
 
 inline void ReverseString(const nsString& aInput, nsAString& aReversed)
 {
@@ -5923,7 +5924,7 @@ nsNavHistory::FilterResultSet(nsNavHistoryQueryResultNode* aQueryNode,
   NS_ENSURE_TRUE(bookmarks, NS_ERROR_OUT_OF_MEMORY);
 
   // parse the search terms
-  nsTArray<nsStringArray*> terms;
+  nsTArray<nsTArray<nsString>*> terms;
   ParseSearchTermsFromQueries(aQueries, &terms);
 
   PRInt32 queryIndex;
@@ -5989,7 +5990,7 @@ nsNavHistory::FilterResultSet(nsNavHistoryQueryResultNode* aQueryNode,
 
     // if we are excluding items by parent annotation, 
     // exclude items who's parent is a folder with that annotation
-    if (!parentAnnotationToExclude.IsEmpty() && (parentFoldersToExclude.IndexOf(parentId) != -1))
+    if (!parentAnnotationToExclude.IsEmpty() && parentFoldersToExclude.Contains(parentId))
       continue;
 
     // Append the node if it matches one of the queries
@@ -6007,10 +6008,10 @@ nsNavHistory::FilterResultSet(nsNavHistoryQueryResultNode* aQueryNode,
 
         // filter out the node of which their parent is in the exclude-folders
         // cache
-        if (excludeFolders[queryIndex]->IndexOf(parentId) != -1)
+        if (excludeFolders[queryIndex]->Contains(parentId))
           continue;
 
-        if (includeFolders[queryIndex]->IndexOf(parentId) == -1) {
+        if (!includeFolders[queryIndex]->Contains(parentId)) {
           // check ancestors
           PRInt64 ancestor = parentId, lastAncestor;
           PRBool belongs = PR_FALSE;
@@ -6024,9 +6025,9 @@ nsNavHistory::FilterResultSet(nsNavHistoryQueryResultNode* aQueryNode,
             // GetFolderIdForItems throws when called for the places-root
             if (NS_FAILED(bookmarks->GetFolderIdForItem(ancestor,&ancestor))) {
               break;
-            } else if (excludeFolders[queryIndex]->IndexOf(ancestor) != -1) {
+            } else if (excludeFolders[queryIndex]->Contains(ancestor)) {
               break;
-            } else if (includeFolders[queryIndex]->IndexOf(ancestor) != -1) {
+            } else if (includeFolders[queryIndex]->Contains(ancestor)) {
               belongs = PR_TRUE;
             }
           }
@@ -6065,14 +6066,14 @@ nsNavHistory::FilterResultSet(nsNavHistoryQueryResultNode* aQueryNode,
 
       // Determine if every search term matches anywhere in the title, url, tag
       PRBool matchAll = PR_TRUE;
-      for (PRInt32 termIndex = terms[queryIndex]->Count(); --termIndex >= 0 &&
+      for (PRInt32 termIndex = terms[queryIndex]->Length(); --termIndex >= 0 &&
            matchAll; ) {
-        const nsString *term = terms[queryIndex]->StringAt(termIndex);
+        const nsString& term = terms[queryIndex]->ElementAt(termIndex);
 
         // True if any of them match; false makes us quit the loop
-        matchAll = CaseInsensitiveFindInReadable(*term, nodeTitle) ||
-                   CaseInsensitiveFindInReadable(*term, nodeURL) ||
-                   CaseInsensitiveFindInReadable(*term, nodeTags);
+        matchAll = CaseInsensitiveFindInReadable(term, nodeTitle) ||
+                   CaseInsensitiveFindInReadable(term, nodeURL) ||
+                   CaseInsensitiveFindInReadable(term, nodeTags);
       }
 
       // Skip if we don't match all terms in the title, url or tag
@@ -6892,11 +6893,11 @@ inline PRBool isQueryWhitespace(PRUnichar ch)
 }
 
 void ParseSearchTermsFromQueries(const nsCOMArray<nsNavHistoryQuery>& aQueries,
-                                 nsTArray<nsStringArray*>* aTerms)
+                                 nsTArray<nsTArray<nsString>*>* aTerms)
 {
   PRInt32 lastBegin = -1;
   for (PRUint32 i=0; i < aQueries.Count(); i++) {
-    nsStringArray *queryTerms = new nsStringArray();
+    nsTArray<nsString> *queryTerms = new nsTArray<nsString>();
     PRBool hasSearchTerms;
     if (NS_SUCCEEDED(aQueries[i]->GetHasSearchTerms(&hasSearchTerms)) &&
         hasSearchTerms) {
@@ -6906,7 +6907,7 @@ void ParseSearchTermsFromQueries(const nsCOMArray<nsNavHistoryQuery>& aQueries,
             searchTerms[j] == '"') {
           if (lastBegin >= 0) {
             // found the end of a word
-            queryTerms->AppendString(Substring(searchTerms, lastBegin,
+            queryTerms->AppendElement(Substring(searchTerms, lastBegin,
                                                j - lastBegin));
             lastBegin = -1;
           }
@@ -6919,7 +6920,7 @@ void ParseSearchTermsFromQueries(const nsCOMArray<nsNavHistoryQuery>& aQueries,
       }
       // last word
       if (lastBegin >= 0)
-        queryTerms->AppendString(Substring(searchTerms, lastBegin));
+        queryTerms->AppendElement(Substring(searchTerms, lastBegin));
     }
     aTerms->AppendElement(queryTerms);
   }
diff --git a/toolkit/components/places/src/nsNavHistory.h b/toolkit/components/places/src/nsNavHistory.h
index a5485b1cce7..e8a3cf4d57f 100644
--- a/toolkit/components/places/src/nsNavHistory.h
+++ b/toolkit/components/places/src/nsNavHistory.h
@@ -740,7 +740,7 @@ protected:
   nsString mOrigSearchString;
   // Search string and tokens for case-insensitive matching
   nsString mCurrentSearchString;
-  nsStringArray mCurrentSearchTokens;
+  nsTArray<nsString> mCurrentSearchTokens;
   void GenerateSearchTokens();
   void AddSearchToken(nsAutoString &aToken);
   void ProcessTokensForSpecialSearch();
diff --git a/toolkit/components/places/src/nsNavHistoryAutoComplete.cpp b/toolkit/components/places/src/nsNavHistoryAutoComplete.cpp
index fcbbbf5bc0f..98e3d1507bc 100644
--- a/toolkit/components/places/src/nsNavHistoryAutoComplete.cpp
+++ b/toolkit/components/places/src/nsNavHistoryAutoComplete.cpp
@@ -236,20 +236,20 @@ StartsWithJS(const nsAString &aString)
 
 /**
  * Callback function for putting URLs from a nsDataHashtable<nsStringHashKey,
- * PRBool> into a nsStringArray.
+ * PRBool> into a nsTArray<nsString>.
  *
  * @param aKey
  *        The hashtable entry's key (the url)
  * @param aData
  *        Unused data
  * @param aArg
- *        The nsStringArray pointer for collecting URLs
+ *        The nsTArray<nsString> pointer for collecting URLs
  */
 PLDHashOperator
 HashedURLsToArray(const nsAString &aKey, PRBool aData, void *aArg)
 {
   // Append the current url to the array of urls
-  static_cast<nsStringArray *>(aArg)->AppendString(aKey);
+  static_cast<nsTArray<nsString> *>(aArg)->AppendElement(aKey);
   return PL_DHASH_NEXT;
 }
 
@@ -570,7 +570,7 @@ nsNavHistory::PerformAutoComplete()
   // Only do some extra searches on the first chunk
   if (!mCurrentChunkOffset) {
     // Only show keywords if there's a search
-    if (mCurrentSearchTokens.Count()) {
+    if (mCurrentSearchTokens.Length()) {
       rv = AutoCompleteKeywordSearch();
       NS_ENSURE_SUCCESS(rv, rv);
     }
@@ -757,12 +757,12 @@ nsNavHistory::StartSearch(const nsAString & aSearchString,
       NS_ENSURE_SUCCESS(rv, rv);
 
       // Collect the previous result's URLs that we want to process
-      nsStringArray urls;
+      nsTArray<nsString> urls;
       (void)mCurrentResultURLs.EnumerateRead(HashedURLsToArray, &urls);
 
       // Bind the parameters right away. We can only use the query once.
       for (PRUint32 i = 0; i < prevMatchCount; i++) {
-        rv = mDBPreviousQuery->BindStringParameter(i + 1, *urls[i]);
+        rv = mDBPreviousQuery->BindStringParameter(i + 1, urls[i]);
         NS_ENSURE_SUCCESS(rv, rv);
       }
 
@@ -862,7 +862,7 @@ nsNavHistory::AddSearchToken(nsAutoString &aToken)
 {
   aToken.Trim("\r\n\t\b");
   if (!aToken.IsEmpty())
-    mCurrentSearchTokens.AppendString(aToken);
+    mCurrentSearchTokens.AppendElement(aToken);
 }
 
 void
@@ -879,28 +879,28 @@ nsNavHistory::ProcessTokensForSpecialSearch()
   // SEARCH_BOTH doesn't require any filtering
 
   // Determine which special searches to apply
-  for (PRInt32 i = mCurrentSearchTokens.Count(); --i >= 0; ) {
+  for (PRInt32 i = PRInt32(mCurrentSearchTokens.Length()); --i >= 0;) {
     PRBool needToRemove = PR_TRUE;
-    const nsString *token = mCurrentSearchTokens.StringAt(i);
+    const nsString& token = mCurrentSearchTokens[i];
 
-    if (token->Equals(mAutoCompleteRestrictHistory))
+    if (token.Equals(mAutoCompleteRestrictHistory))
       SET_BEHAVIOR(History);
-    else if (token->Equals(mAutoCompleteRestrictBookmark))
+    else if (token.Equals(mAutoCompleteRestrictBookmark))
       SET_BEHAVIOR(Bookmark);
-    else if (token->Equals(mAutoCompleteRestrictTag))
+    else if (token.Equals(mAutoCompleteRestrictTag))
       SET_BEHAVIOR(Tag);
-    else if (token->Equals(mAutoCompleteMatchTitle))
+    else if (token.Equals(mAutoCompleteMatchTitle))
       SET_BEHAVIOR(Title);
-    else if (token->Equals(mAutoCompleteMatchUrl))
+    else if (token.Equals(mAutoCompleteMatchUrl))
       SET_BEHAVIOR(Url);
-    else if (token->Equals(mAutoCompleteRestrictTyped))
+    else if (token.Equals(mAutoCompleteRestrictTyped))
       SET_BEHAVIOR(Typed);
     else
       needToRemove = PR_FALSE;
 
     // Remove the token if it's special search token
     if (needToRemove)
-      (void)mCurrentSearchTokens.RemoveStringAt(i);
+      mCurrentSearchTokens.RemoveElementAt(i);
   }
 
   // Search only typed pages in history for empty searches
@@ -1119,13 +1119,13 @@ nsNavHistory::AutoCompleteProcessSearch(mozIStorageStatement* aQuery,
 
           // Determine if every token matches either the bookmark title, tags,
           // page title, or page url
-          for (PRInt32 i = 0; i < mCurrentSearchTokens.Count() && matchAll; i++) {
-            const nsString *token = mCurrentSearchTokens.StringAt(i);
+          for (PRUint32 i = 0; i < mCurrentSearchTokens.Length() && matchAll; i++) {
+            const nsString& token = mCurrentSearchTokens[i];
 
             // Check if the tags match the search term
-            PRBool matchTags = (*tokenMatchesTarget)(*token, entryTags);
+            PRBool matchTags = (*tokenMatchesTarget)(token, entryTags);
             // Check if the title matches the search term
-            PRBool matchTitle = (*tokenMatchesTarget)(*token, title);
+            PRBool matchTitle = (*tokenMatchesTarget)(token, title);
 
             // Make sure we match something in the title or tags if we have to
             matchAll = matchTags || matchTitle;
@@ -1133,7 +1133,7 @@ nsNavHistory::AutoCompleteProcessSearch(mozIStorageStatement* aQuery,
               break;
 
             // Check if the url matches the search term
-            PRBool matchUrl = (*tokenMatchesTarget)(*token, entryURL);
+            PRBool matchUrl = (*tokenMatchesTarget)(token, entryURL);
             // If we don't match the url when we have to, reset matchAll to
             // false; otherwise keep track that we did match the current search
             if (GET_BEHAVIOR(Url) && !matchUrl)
diff --git a/tools/relic/test/relicense_inputs/need_to_relicense.h b/tools/relic/test/relicense_inputs/need_to_relicense.h
index 5691db2b3e0..6bc02a580e9 100755
--- a/tools/relic/test/relicense_inputs/need_to_relicense.h
+++ b/tools/relic/test/relicense_inputs/need_to_relicense.h
@@ -49,6 +49,7 @@
 #include "ChangeCSSInlineStyleTxn.h"
 #include "nsEditProperty.h"
 #include "nsIDOMCSSStyleDeclaration.h"
+#include "nsTArray.h"
 
 #define SPECIFIED_STYLE_TYPE    1
 #define COMPUTED_STYLE_TYPE     2
@@ -337,7 +338,7 @@ private:
     */
 
   void      BuildCSSDeclarations(nsVoidArray & aPropertyArray,
-                                 nsStringArray & cssValueArray,
+                                 nsTArray<nsString> & cssValueArray,
                                  const CSSEquivTable * aEquivTable,
                                  const nsAString * aValue,
                                  PRBool aGetOrRemoveRequest);
@@ -360,7 +361,7 @@ private:
                                                  const nsAString *aAttribute,
                                                  const nsAString *aValue,
                                                  nsVoidArray & aPropertyArray,
-                                                 nsStringArray & aValueArray,
+                                                 nsTArray<nsString> & aValueArray,
                                                  PRBool aGetOrRemoveRequest);
 
   /** creates a Transaction for setting or removing a css property
diff --git a/tools/relic/test/relicense_inputs/npl.h b/tools/relic/test/relicense_inputs/npl.h
index b71071e78bb..c5db9926263 100755
--- a/tools/relic/test/relicense_inputs/npl.h
+++ b/tools/relic/test/relicense_inputs/npl.h
@@ -34,6 +34,7 @@
 #include "ChangeCSSInlineStyleTxn.h"
 #include "nsEditProperty.h"
 #include "nsIDOMCSSStyleDeclaration.h"
+#include "nsTArray.h"
 
 #define SPECIFIED_STYLE_TYPE    1
 #define COMPUTED_STYLE_TYPE     2
@@ -322,7 +323,7 @@ private:
     */
 
   void      BuildCSSDeclarations(nsVoidArray & aPropertyArray,
-                                 nsStringArray & cssValueArray,
+                                 nsTArray<nsString> & cssValueArray,
                                  const CSSEquivTable * aEquivTable,
                                  const nsAString * aValue,
                                  PRBool aGetOrRemoveRequest);
@@ -345,7 +346,7 @@ private:
                                                  const nsAString *aAttribute,
                                                  const nsAString *aValue,
                                                  nsVoidArray & aPropertyArray,
-                                                 nsStringArray & aValueArray,
+                                                 nsTArray<nsString> & aValueArray,
                                                  PRBool aGetOrRemoveRequest);
 
   /** creates a Transaction for setting or removing a css property
diff --git a/tools/relic/test/relicense_outputs/need_to_relicense.h b/tools/relic/test/relicense_outputs/need_to_relicense.h
index bafc5805c61..11a7c44bebf 100755
--- a/tools/relic/test/relicense_outputs/need_to_relicense.h
+++ b/tools/relic/test/relicense_outputs/need_to_relicense.h
@@ -41,6 +41,7 @@
 
 #include "nsCOMPtr.h"
 #include "nsString.h"
+#include "nsTArray.h"
 #include "nsIDOMViewCSS.h"
 #include "nsIDOMNode.h"
 #include "nsIDOMElement.h"
@@ -336,7 +337,7 @@ private:
     */
 
   void      BuildCSSDeclarations(nsVoidArray & aPropertyArray,
-                                 nsStringArray & cssValueArray,
+                                 nsTArray<nsString> & cssValueArray,
                                  const CSSEquivTable * aEquivTable,
                                  const nsAString * aValue,
                                  PRBool aGetOrRemoveRequest);
@@ -359,7 +360,7 @@ private:
                                                  const nsAString *aAttribute,
                                                  const nsAString *aValue,
                                                  nsVoidArray & aPropertyArray,
-                                                 nsStringArray & aValueArray,
+                                                 nsTArray<nsString> & aValueArray,
                                                  PRBool aGetOrRemoveRequest);
 
   /** creates a Transaction for setting or removing a css property
diff --git a/tools/relic/test/relicense_outputs/npl.h b/tools/relic/test/relicense_outputs/npl.h
index cdec11e2d53..63e5267360e 100755
--- a/tools/relic/test/relicense_outputs/npl.h
+++ b/tools/relic/test/relicense_outputs/npl.h
@@ -41,6 +41,7 @@
 
 #include "nsCOMPtr.h"
 #include "nsString.h"
+#include "nsTArray.h"
 #include "nsIDOMViewCSS.h"
 #include "nsIDOMNode.h"
 #include "nsIDOMElement.h"
@@ -336,7 +337,7 @@ private:
     */
 
   void      BuildCSSDeclarations(nsVoidArray & aPropertyArray,
-                                 nsStringArray & cssValueArray,
+                                 nsTArray<nsString> & cssValueArray,
                                  const CSSEquivTable * aEquivTable,
                                  const nsAString * aValue,
                                  PRBool aGetOrRemoveRequest);
@@ -359,7 +360,7 @@ private:
                                                  const nsAString *aAttribute,
                                                  const nsAString *aValue,
                                                  nsVoidArray & aPropertyArray,
-                                                 nsStringArray & aValueArray,
+                                                 nsTArray<nsString> & aValueArray,
                                                  PRBool aGetOrRemoveRequest);
 
   /** creates a Transaction for setting or removing a css property
diff --git a/widget/src/beos/nsDeviceContextSpecB.cpp b/widget/src/beos/nsDeviceContextSpecB.cpp
index 3ac1a7f9287..d414ef49ec2 100644
--- a/widget/src/beos/nsDeviceContextSpecB.cpp
+++ b/widget/src/beos/nsDeviceContextSpecB.cpp
@@ -45,6 +45,7 @@
 #include "nsIServiceManager.h"
 #include "nsReadableUtils.h"
 #include "nsStringEnumerator.h"
+#include "nsTArray.h"
 #include "nsCRT.h"
 
 //----------------------------------------------------------------------------------
@@ -69,14 +70,14 @@ protected:
   GlobalPrinters() {}
 
   static GlobalPrinters mGlobalPrinters;
-  static nsStringArray* mGlobalPrinterList;
+  static nsTArray<nsString>* mGlobalPrinterList;
   static int            mGlobalNumPrinters;
 
 };
 //---------------
 // static members
 GlobalPrinters GlobalPrinters::mGlobalPrinters;
-nsStringArray* GlobalPrinters::mGlobalPrinterList = nsnull;
+nsTArray<nsString>* GlobalPrinters::mGlobalPrinterList = nsnull;
 int            GlobalPrinters::mGlobalNumPrinters = 0;
 
 nsDeviceContextSpecBeOS::nsDeviceContextSpecBeOS()
@@ -151,7 +152,7 @@ NS_IMETHODIMP nsPrinterEnumeratorBeOS::GetPrinterNameList(nsIStringEnumerator **
   }
 
   PRInt32 numPrinters = GlobalPrinters::GetInstance()->GetNumPrinters();
-  nsStringArray *printers = new nsStringArray(numPrinters);
+  nsTArray<nsString> *printers = new nsTArray<nsString>(numPrinters);
   if (!printers) {
     GlobalPrinters::GetInstance()->FreeGlobalPrinters();
     return NS_ERROR_OUT_OF_MEMORY;
@@ -160,7 +161,7 @@ NS_IMETHODIMP nsPrinterEnumeratorBeOS::GetPrinterNameList(nsIStringEnumerator **
   int count = 0;
   while( count < numPrinters )
   {
-    printers->AppendString(*GlobalPrinters::GetInstance()->GetStringAt(count++));
+    printers->AppendElement(*GlobalPrinters::GetInstance()->GetStringAt(count++));
   }
   GlobalPrinters::GetInstance()->FreeGlobalPrinters();
 
@@ -195,12 +196,12 @@ nsresult GlobalPrinters::InitializeGlobalPrinters ()
   mGlobalNumPrinters = 0;
 
 #ifdef USE_POSTSCRIPT
-  mGlobalPrinterList = new nsStringArray();
+  mGlobalPrinterList = new nsTArray<nsString>();
   if (!mGlobalPrinterList) 
     return NS_ERROR_OUT_OF_MEMORY;
 
   /* add an entry for the default printer (see nsPostScriptObj.cpp) */
-  mGlobalPrinterList->AppendString(
+  mGlobalPrinterList->AppendElement(
     nsString(NS_ConvertASCIItoUTF16(NS_POSTSCRIPT_DRIVER_NAME "default")));
   mGlobalNumPrinters++;
 
@@ -232,7 +233,7 @@ nsresult GlobalPrinters::InitializeGlobalPrinters ()
          name != nsnull ; 
          name = PL_strtok_r(nsnull, " ", &tok_lasts) )
     {
-      mGlobalPrinterList->AppendString(
+      mGlobalPrinterList->AppendElement(
         nsString(NS_ConvertASCIItoUTF16(NS_POSTSCRIPT_DRIVER_NAME)) + 
         nsString(NS_ConvertASCIItoUTF16(name)));
       mGlobalNumPrinters++;      
diff --git a/widget/src/cocoa/nsFilePicker.h b/widget/src/cocoa/nsFilePicker.h
index ddc6a10f0cf..c161ffee8fa 100644
--- a/widget/src/cocoa/nsFilePicker.h
+++ b/widget/src/cocoa/nsFilePicker.h
@@ -48,6 +48,7 @@
 #include "nsIFileChannel.h"
 #include "nsILocalFile.h"
 #include "nsCOMArray.h"
+#include "nsTArray.h"
 
 class nsILocalFileMac;
 @class NSArray;
@@ -101,8 +102,8 @@ protected:
   nsCOMArray<nsILocalFile> mFiles;
   nsString               mDefault;
 
-  nsStringArray          mFilters; 
-  nsStringArray          mTitles;
+  nsTArray<nsString>     mFilters; 
+  nsTArray<nsString>     mTitles;
 
   PRInt32                mSelectedTypeIndex;
 };
diff --git a/widget/src/cocoa/nsFilePicker.mm b/widget/src/cocoa/nsFilePicker.mm
index 61869c46709..5e0dd57a0b8 100644
--- a/widget/src/cocoa/nsFilePicker.mm
+++ b/widget/src/cocoa/nsFilePicker.mm
@@ -125,12 +125,12 @@ NSView* nsFilePicker::GetAccessoryView()
 
   // set up popup button
   NSPopUpButton* popupButton = [[[NSPopUpButton alloc] initWithFrame:NSMakeRect(0, 0, 0, 0) pullsDown:NO] autorelease];
-  PRInt32 numMenuItems = mTitles.Count();
+  PRInt32 numMenuItems = mTitles.Length();
   for (int i = 0; i < numMenuItems; i++) {
-    const nsString& currentTitle = *mTitles[i];
+    const nsString& currentTitle = mTitles[i];
     NSString *titleString;
     if (currentTitle.IsEmpty()) {
-      const nsString& currentFilter = *mFilters[i];
+      const nsString& currentFilter = mFilters[i];
       titleString = [[NSString alloc] initWithCharacters:currentFilter.get()
                                                   length:currentFilter.Length()];
     }
@@ -418,25 +418,25 @@ nsFilePicker::GenerateFilterList()
   NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NIL;
 
   NSArray *filterArray = nil;
-  if (mFilters.Count() > 0) {
+  if (mFilters.Length() > 0) {
     // Set up our filter string
     NSMutableString *giantFilterString = [[[NSMutableString alloc] initWithString:@""] autorelease];
 
     // Loop through each of the filter strings
-    for (PRInt32 loop = 0; loop < mFilters.Count(); loop++) {
-      nsString *filterWide = mFilters[loop];
+    for (PRInt32 loop = 0; PRInt32(loop < mFilters.Length()); loop++) {
+      const nsString& filterWide = mFilters[loop];
 
       // separate individual filters
       if ([giantFilterString length] > 0)
         [giantFilterString appendString:[NSString stringWithString:@";"]];
 
       // handle special case filters
-      if (filterWide->Equals(NS_LITERAL_STRING("*"))) {
+      if (filterWide.Equals(NS_LITERAL_STRING("*"))) {
         // if we'll allow all files, we won't bother parsing all other
         // file types. just return early.
         return nil;
       }
-      else if (filterWide->Equals(NS_LITERAL_STRING("..apps"))) {
+      else if (filterWide.Equals(NS_LITERAL_STRING("..apps"))) {
         // this magic filter means that we should enable app bundles.
         // translate it into a usable filter, and continue looping through 
         // other filters.
@@ -444,8 +444,8 @@ nsFilePicker::GenerateFilterList()
         continue;
       }
       
-      if (filterWide && filterWide->Length() > 0)
-        [giantFilterString appendString:[NSString stringWithCharacters:filterWide->get() length:filterWide->Length()]];
+      if (filterWide && filterWide.Length() > 0)
+        [giantFilterString appendString:[NSString stringWithCharacters:filterWide.get() length:filterWide.Length()]];
     }
     
     // Now we clean stuff up.  Get rid of white spaces, "*"'s, and the odd period or two.
@@ -563,8 +563,8 @@ NS_IMETHODIMP nsFilePicker::SetDefaultExtension(const nsAString& aExtension)
 NS_IMETHODIMP
 nsFilePicker::AppendFilter(const nsAString& aTitle, const nsAString& aFilter)
 {
-  mFilters.AppendString(aFilter);
-  mTitles.AppendString(aTitle);
+  mFilters.AppendElement(aFilter);
+  mTitles.AppendElemet(aTitle);
   
   return NS_OK;
 }
diff --git a/widget/src/gtk2/nsDeviceContextSpecG.cpp b/widget/src/gtk2/nsDeviceContextSpecG.cpp
index a1cac582d5d..f52635aba68 100644
--- a/widget/src/gtk2/nsDeviceContextSpecG.cpp
+++ b/widget/src/gtk2/nsDeviceContextSpecG.cpp
@@ -71,6 +71,7 @@
 
 #include "nsIFileStreams.h"
 #include "nsILocalFile.h"
+#include "nsTArray.h"
 
 #include <unistd.h>
 #include <sys/types.h>
@@ -101,15 +102,15 @@ public:
 
   PRBool    PrintersAreAllocated()       { return mGlobalPrinterList != nsnull; }
   PRInt32   GetNumPrinters()
-    { return mGlobalPrinterList ? mGlobalPrinterList->Count() : 0; }
-  nsString* GetStringAt(PRInt32 aInx)    { return mGlobalPrinterList->StringAt(aInx); }
+    { return mGlobalPrinterList ? mGlobalPrinterList->Length() : 0; }
+  nsString* GetStringAt(PRInt32 aInx)    { return &mGlobalPrinterList->ElementAt(aInx); }
   void      GetDefaultPrinterName(PRUnichar **aDefaultPrinterName);
 
 protected:
   GlobalPrinters() {}
 
   static GlobalPrinters mGlobalPrinters;
-  static nsStringArray* mGlobalPrinterList;
+  static nsTArray<nsString>* mGlobalPrinterList;
 };
 
 #ifdef SET_PRINTER_FEATURES_VIA_PREFS
@@ -380,7 +381,7 @@ void nsPrinterFeatures::SetMultipleConcurrentDeviceContextsSupported( PRBool aCa
 //---------------
 // static members
 GlobalPrinters GlobalPrinters::mGlobalPrinters;
-nsStringArray* GlobalPrinters::mGlobalPrinterList = nsnull;
+nsTArray<nsString>* GlobalPrinters::mGlobalPrinterList = nsnull;
 //---------------
 
 nsDeviceContextSpecGTK::nsDeviceContextSpecGTK()
@@ -831,7 +832,7 @@ NS_IMETHODIMP nsPrinterEnumeratorGTK::GetPrinterNameList(nsIStringEnumerator **a
   }
 
   PRInt32 numPrinters = GlobalPrinters::GetInstance()->GetNumPrinters();
-  nsStringArray *printers = new nsStringArray(numPrinters);
+  nsTArray<nsString> *printers = new nsTArray<nsString>(numPrinters);
   if (!printers) {
     GlobalPrinters::GetInstance()->FreeGlobalPrinters();
     return NS_ERROR_OUT_OF_MEMORY;
@@ -840,7 +841,7 @@ NS_IMETHODIMP nsPrinterEnumeratorGTK::GetPrinterNameList(nsIStringEnumerator **a
   int count = 0;
   while( count < numPrinters )
   {
-    printers->AppendString(*GlobalPrinters::GetInstance()->GetStringAt(count++));
+    printers->AppendElement(*GlobalPrinters::GetInstance()->GetStringAt(count++));
   }
   GlobalPrinters::GetInstance()->FreeGlobalPrinters();
 
@@ -1075,8 +1076,8 @@ NS_IMETHODIMP nsPrinterEnumeratorGTK::DisplayPropertiesDlg(const PRUnichar *aPri
 static PRBool
 GlobalPrinterEnumFunc(nsCString& aName, void *aData)
 {
-  nsStringArray *a = (nsStringArray *)aData;
-  a->AppendString(NS_ConvertUTF8toUTF16(aName));
+  nsTArray<nsString> *a = (nsTArray<nsString> *)aData;
+  a->AppendElement(NS_ConvertUTF8toUTF16(aName));
   return PR_TRUE;
 }
 
@@ -1087,7 +1088,7 @@ nsresult GlobalPrinters::InitializeGlobalPrinters ()
     return NS_OK;
   }
 
-  mGlobalPrinterList = new nsStringArray();
+  mGlobalPrinterList = new nsTArray<nsString>();
   if (!mGlobalPrinterList) 
     return NS_ERROR_OUT_OF_MEMORY;
 
@@ -1107,7 +1108,7 @@ nsresult GlobalPrinters::InitializeGlobalPrinters ()
 #endif /* USE_POSTSCRIPT */  
       
   /* If there are no printers available after all checks, return an error */
-  if (!mGlobalPrinterList->Count())
+  if (!mGlobalPrinterList->Length())
   {
     /* Make sure we do not cache an empty printer list */
     FreeGlobalPrinters();
diff --git a/widget/src/os2/nsDeviceContextSpecOS2.cpp b/widget/src/os2/nsDeviceContextSpecOS2.cpp
index 194c50935db..ff7ad318f80 100644
--- a/widget/src/os2/nsDeviceContextSpecOS2.cpp
+++ b/widget/src/os2/nsDeviceContextSpecOS2.cpp
@@ -43,6 +43,7 @@
 
 #include "nsReadableUtils.h"
 #include "nsISupportsArray.h"
+#include "nsTArray.h"
 
 #include "nsIPrefService.h"
 #include "nsIPrefBranch.h"
@@ -89,14 +90,14 @@ protected:
   GlobalPrinters() {}
 
   static GlobalPrinters mGlobalPrinters;
-  static nsStringArray* mGlobalPrinterList;
+  static nsTArray<nsString>* mGlobalPrinterList;
   static ULONG          mGlobalNumPrinters;
 
 };
 //---------------
 // static members
 GlobalPrinters GlobalPrinters::mGlobalPrinters;
-nsStringArray* GlobalPrinters::mGlobalPrinterList = nsnull;
+nsTArray<nsString>* GlobalPrinters::mGlobalPrinterList = nsnull;
 ULONG          GlobalPrinters::mGlobalNumPrinters = 0;
 //---------------
 
@@ -575,7 +576,7 @@ NS_IMETHODIMP nsPrinterEnumeratorOS2::GetPrinterNameList(nsIStringEnumerator **a
   }
 
   ULONG numPrinters = GlobalPrinters::GetInstance()->GetNumPrinters();
-  nsStringArray *printers = new nsStringArray(numPrinters);
+  nsTArray<nsString> *printers = new nsTArray<nsString>(numPrinters);
   if (!printers) {
     GlobalPrinters::GetInstance()->FreeGlobalPrinters();
     return NS_ERROR_OUT_OF_MEMORY;
@@ -584,7 +585,7 @@ NS_IMETHODIMP nsPrinterEnumeratorOS2::GetPrinterNameList(nsIStringEnumerator **a
   ULONG count = 0;
   while( count < numPrinters )
   {
-    printers->AppendString(*GlobalPrinters::GetInstance()->GetStringAt(count++));
+    printers->AppendElement(*GlobalPrinters::GetInstance()->GetStringAt(count++));
   }
   GlobalPrinters::GetInstance()->FreeGlobalPrinters();
 
@@ -654,7 +655,7 @@ nsresult GlobalPrinters::InitializeGlobalPrinters ()
   if (!mGlobalNumPrinters) 
     return NS_ERROR_GFX_PRINTER_NO_PRINTER_AVAILABLE; 
 
-  mGlobalPrinterList = new nsStringArray();
+  mGlobalPrinterList = new nsTArray<nsString>();
   if (!mGlobalPrinterList) 
      return NS_ERROR_OUT_OF_MEMORY;
 
@@ -670,7 +671,7 @@ nsresult GlobalPrinters::InitializeGlobalPrinters ()
     PRInt32 printerNameLength;
     rv = MultiByteToWideChar(0, printer, strlen(printer),
                              printerName, printerNameLength);
-    mGlobalPrinterList->AppendString(nsDependentString(printerName.Elements()));
+    mGlobalPrinterList->AppendElement(nsDependentString(printerName.Elements()));
 
     // store printer description in prefs for the print dialog
     if (!prefFailed) {
diff --git a/widget/src/os2/nsFilePicker.cpp b/widget/src/os2/nsFilePicker.cpp
index 963f0a87f6a..79b1bc834a2 100644
--- a/widget/src/os2/nsFilePicker.cpp
+++ b/widget/src/os2/nsFilePicker.cpp
@@ -189,13 +189,13 @@ NS_IMETHODIMP nsFilePicker::Show(PRInt16 *retval)
     filedlg.ulUser = (ULONG)pmydata;
     filedlg.pfnDlgProc = FileDialogProc;
 
-    int i;
+    PRUint32 i;
 
     PSZ *apszTypeList;
-    apszTypeList = (PSZ *)malloc(mTitles.Count()*sizeof(PSZ)+1);
-    for (i = 0; i < mTitles.Count(); i++)
+    apszTypeList = (PSZ *)malloc(mTitles.Length()*sizeof(PSZ)+1);
+    for (i = 0; i < mTitles.Length(); i++)
     {
-      const nsString& typeWide = *mTitles[i];
+      const nsString& typeWide = mTitles[i];
       nsAutoCharBuffer buffer;
       PRInt32 bufLength;
       WideCharToMultiByte(0, typeWide.get(), typeWide.Length(),
@@ -206,10 +206,10 @@ NS_IMETHODIMP nsFilePicker::Show(PRInt16 *retval)
     filedlg.papszITypeList = (PAPSZ)apszTypeList;
 
     PSZ *apszFilterList;
-    apszFilterList = (PSZ *)malloc(mFilters.Count()*sizeof(PSZ)+1);
-    for (i = 0; i < mFilters.Count(); i++)
+    apszFilterList = (PSZ *)malloc(mFilters.Length()*sizeof(PSZ)+1);
+    for (i = 0; i < mFilters.Length(); i++)
     {
-      const nsString& filterWide = *mFilters[i];
+      const nsString& filterWide = mFilters[i];
       apszFilterList[i] = ToNewCString(filterWide);
     }
     apszFilterList[i] = 0;
@@ -319,13 +319,13 @@ NS_IMETHODIMP nsFilePicker::Show(PRInt16 *retval)
       mSelectedType = (PRInt16)pmydata->ulCurExt;
     }
 
-    for (i = 0; i < mTitles.Count(); i++)
+    for (i = 0; i < mTitles.Length(); i++)
     {
       nsMemory::Free(*(filedlg.papszITypeList[i]));
     }
     free(filedlg.papszITypeList);
 
-    for (i = 0; i < mFilters.Count(); i++)
+    for (i = 0; i < mFilters.Length(); i++)
     {
       nsMemory::Free(*(pmydata->papszIFilterList[i]));
     }
@@ -616,10 +616,10 @@ NS_IMETHODIMP
 nsFilePicker::AppendFilter(const nsAString& aTitle, const nsAString& aFilter)
 {
   if (aFilter.EqualsLiteral("..apps"))
-    mFilters.AppendString(NS_LITERAL_STRING("*.exe;*.cmd;*.com;*.bat"));
+    mFilters.AppendElement(NS_LITERAL_STRING("*.exe;*.cmd;*.com;*.bat"));
   else
-    mFilters.AppendString(aFilter);
-  mTitles.AppendString(aTitle);
+    mFilters.AppendElement(aFilter);
+  mTitles.AppendElement(aTitle);
 
   return NS_OK;
 }
diff --git a/widget/src/os2/nsFilePicker.h b/widget/src/os2/nsFilePicker.h
index d903bd78674..ee1d04d9167 100644
--- a/widget/src/os2/nsFilePicker.h
+++ b/widget/src/os2/nsFilePicker.h
@@ -42,6 +42,7 @@
 
 #include "nsISimpleEnumerator.h"
 #include "nsISupportsArray.h"
+#include "nsTArray.h"
 
 #include "nsICharsetConverterManager.h"
 #include "nsBaseFilePicker.h"
@@ -92,8 +93,8 @@ protected:
   nsCString              mFile;
   nsString               mDefault;
   nsString               mDefaultExtension;
-  nsStringArray          mFilters;
-  nsStringArray          mTitles;
+  nsTArray<nsString>     mFilters;
+  nsTArray<nsString>     mTitles;
   nsIUnicodeEncoder*     mUnicodeEncoder;
   nsIUnicodeDecoder*     mUnicodeDecoder;
   PRInt16                mSelectedType;
diff --git a/widget/src/windows/nsDeviceContextSpecWin.cpp b/widget/src/windows/nsDeviceContextSpecWin.cpp
index fc3e104f117..4fead8ec14d 100644
--- a/widget/src/windows/nsDeviceContextSpecWin.cpp
+++ b/widget/src/windows/nsDeviceContextSpecWin.cpp
@@ -48,6 +48,7 @@
 #include "nsIWidget.h"
 
 #include "nsVoidArray.h"
+#include "nsTArray.h"
 #include "nsIPrintSettingsWin.h"
 
 #include "nsString.h"
@@ -939,7 +940,7 @@ nsPrinterEnumeratorWin::GetPrinterNameList(nsIStringEnumerator **aPrinterNameLis
   }
 
   PRInt32 numPrinters = GlobalPrinters::GetInstance()->GetNumPrinters();
-  nsStringArray *printers = new nsStringArray(numPrinters);
+  nsTArray<nsString> *printers = new nsTArray<nsString>(numPrinters);
   if (!printers)
     return NS_ERROR_OUT_OF_MEMORY;
 
@@ -952,7 +953,7 @@ nsPrinterEnumeratorWin::GetPrinterNameList(nsIStringEnumerator **aPrinterNameLis
     nsAutoString newName; 
     NS_CopyNativeToUnicode(nsDependentCString(name), newName);
 #endif
-    printers->AppendString(newName);
+    printers->AppendElement(newName);
   }
 
   return NS_NewAdoptingStringEnumerator(aPrinterNameList, printers);
diff --git a/xpcom/ds/nsStringEnumerator.cpp b/xpcom/ds/nsStringEnumerator.cpp
index 3b6d7fd01c9..02d29716db0 100644
--- a/xpcom/ds/nsStringEnumerator.cpp
+++ b/xpcom/ds/nsStringEnumerator.cpp
@@ -54,7 +54,7 @@ class nsStringEnumerator : public nsIStringEnumerator,
                            public nsISimpleEnumerator
 {
 public:
-    nsStringEnumerator(const nsStringArray* aArray, PRBool aOwnsArray) :
+    nsStringEnumerator(const nsTArray<nsString>* aArray, PRBool aOwnsArray) :
         mArray(aArray), mIndex(0), mOwnsArray(aOwnsArray), mIsUnicode(PR_TRUE)
     {}
     
@@ -62,7 +62,7 @@ public:
         mCArray(aArray), mIndex(0), mOwnsArray(aOwnsArray), mIsUnicode(PR_FALSE)
     {}
 
-    nsStringEnumerator(const nsStringArray* aArray, nsISupports* aOwner) :
+    nsStringEnumerator(const nsTArray<nsString>* aArray, nsISupports* aOwner) :
         mArray(aArray), mIndex(0), mOwner(aOwner), mOwnsArray(PR_FALSE), mIsUnicode(PR_TRUE)
     {}
     
@@ -85,19 +85,19 @@ private:
             // constructors make sure mOwnsArray is consistent with
             // the constness of the objects
             if (mIsUnicode)
-                delete const_cast<nsStringArray*>(mArray);
+                delete const_cast<nsTArray<nsString>*>(mArray);
             else
                 delete const_cast<nsCStringArray*>(mCArray);
         }
     }
 
     union {
-        const nsStringArray* mArray;
+        const nsTArray<nsString>* mArray;
         const nsCStringArray* mCArray;
     };
 
     inline PRUint32 Count() {
-        return mIsUnicode ? mArray->Count() : mCArray->Count();
+        return mIsUnicode ? mArray->Length() : mCArray->Count();
     }
     
     PRUint32 mIndex;
@@ -137,7 +137,7 @@ nsStringEnumerator::GetNext(nsISupports** aResult)
         nsSupportsStringImpl* stringImpl = new nsSupportsStringImpl();
         if (!stringImpl) return NS_ERROR_OUT_OF_MEMORY;
         
-        stringImpl->SetData(*mArray->StringAt(mIndex++));
+        stringImpl->SetData(mArray->ElementAt(mIndex++));
         *aResult = stringImpl;
     }
     else {
@@ -157,7 +157,7 @@ nsStringEnumerator::GetNext(nsAString& aResult)
     NS_ENSURE_TRUE(mIndex < Count(), NS_ERROR_UNEXPECTED);
 
     if (mIsUnicode)
-        aResult = *mArray->StringAt(mIndex++);
+        aResult = mArray->ElementAt(mIndex++);
     else
         CopyUTF8toUTF16(*mCArray->CStringAt(mIndex++), aResult);
     
@@ -170,7 +170,7 @@ nsStringEnumerator::GetNext(nsACString& aResult)
     NS_ENSURE_TRUE(mIndex < Count(), NS_ERROR_UNEXPECTED);
     
     if (mIsUnicode)
-        CopyUTF16toUTF8(*mArray->StringAt(mIndex++), aResult);
+        CopyUTF16toUTF8(mArray->ElementAt(mIndex++), aResult);
     else
         aResult = *mCArray->CStringAt(mIndex++);
     
@@ -193,7 +193,7 @@ StringEnumeratorTail(T** aResult NS_INPARAM)
 
 NS_COM nsresult
 NS_NewStringEnumerator(nsIStringEnumerator** aResult,
-                       const nsStringArray* aArray, nsISupports* aOwner)
+                       const nsTArray<nsString>* aArray, nsISupports* aOwner)
 {
     NS_ENSURE_ARG_POINTER(aResult);
     NS_ENSURE_ARG_POINTER(aArray);
@@ -216,7 +216,7 @@ NS_NewUTF8StringEnumerator(nsIUTF8StringEnumerator** aResult,
 
 NS_COM nsresult
 NS_NewAdoptingStringEnumerator(nsIStringEnumerator** aResult,
-                               nsStringArray* aArray)
+                               nsTArray<nsString>* aArray)
 {
     NS_ENSURE_ARG_POINTER(aResult);
     NS_ENSURE_ARG_POINTER(aArray);
@@ -239,7 +239,7 @@ NS_NewAdoptingUTF8StringEnumerator(nsIUTF8StringEnumerator** aResult,
 // const ones internally just forward to the non-const equivalents
 NS_COM nsresult
 NS_NewStringEnumerator(nsIStringEnumerator** aResult,
-                       const nsStringArray* aArray)
+                       const nsTArray<nsString>* aArray)
 {
     NS_ENSURE_ARG_POINTER(aResult);
     NS_ENSURE_ARG_POINTER(aArray);
diff --git a/xpcom/ds/nsStringEnumerator.h b/xpcom/ds/nsStringEnumerator.h
index 34b2ec67a4b..6000b9ed5d2 100644
--- a/xpcom/ds/nsStringEnumerator.h
+++ b/xpcom/ds/nsStringEnumerator.h
@@ -38,6 +38,7 @@
 
 #include "nsIStringEnumerator.h"
 #include "nsVoidArray.h"
+#include "nsTArray.h"
 
 // nsIStringEnumerator/nsIUTF8StringEnumerator implementations
 //
@@ -75,12 +76,16 @@
 // NS_RELEASE(enumerator);
 //
 NS_COM nsresult
+NS_NewStringEnumerator(nsIStringEnumerator** aResult NS_OUTPARAM,
+                       const nsTArray<nsString>* aArray,
+                       nsISupports* aOwner);
+NS_COM nsresult
 NS_NewUTF8StringEnumerator(nsIUTF8StringEnumerator** aResult NS_OUTPARAM,
                            const nsCStringArray* aArray);
 
 NS_COM nsresult
 NS_NewStringEnumerator(nsIStringEnumerator** aResult NS_OUTPARAM,
-                       const nsStringArray* aArray);
+                       const nsTArray<nsString>* aArray);
 
 // Adopting string enumerators assume ownership of the array and will
 // call |operator delete| on the array when the enumerator is destroyed
@@ -93,7 +98,7 @@ NS_NewStringEnumerator(nsIStringEnumerator** aResult NS_OUTPARAM,
 // NS_NewAdoptingStringEnumerator(&result, array);
 NS_COM nsresult
 NS_NewAdoptingStringEnumerator(nsIStringEnumerator** aResult NS_OUTPARAM,
-                               nsStringArray* aArray);
+                               nsTArray<nsString>* aArray);
 
 NS_COM nsresult
 NS_NewAdoptingUTF8StringEnumerator(nsIUTF8StringEnumerator** aResult NS_OUTPARAM,
@@ -113,10 +118,6 @@ NS_NewAdoptingUTF8StringEnumerator(nsIUTF8StringEnumerator** aResult NS_OUTPARAM
 // }
 //
 NS_COM nsresult
-NS_NewStringEnumerator(nsIStringEnumerator** aResult NS_OUTPARAM,
-                       const nsStringArray* aArray,
-                       nsISupports* aOwner);
-NS_COM nsresult
 NS_NewUTF8StringEnumerator(nsIUTF8StringEnumerator** aResult NS_OUTPARAM,
                            const nsCStringArray* aArray,
                            nsISupports* aOwner);
diff --git a/xpcom/io/nsLocalFileOSX.mm b/xpcom/io/nsLocalFileOSX.mm
index 19274032d05..f054a867d01 100644
--- a/xpcom/io/nsLocalFileOSX.mm
+++ b/xpcom/io/nsLocalFileOSX.mm
@@ -50,6 +50,7 @@
 #include "nsISimpleEnumerator.h"
 #include "nsITimelineService.h"
 #include "nsVoidArray.h"
+#include "nsTArray.h"
 
 #include "plbase64.h"
 #include "prmem.h"
@@ -456,7 +457,7 @@ NS_IMETHODIMP nsLocalFile::Create(PRUint32 type, PRUint32 permissions)
   // Check we are correctly initialized.
   CHECK_mBaseRef();
   
-  nsStringArray nonExtantNodes;
+  nsTArray<nsString> nonExtantNodes;
   CFURLRef pathURLRef = mBaseRef;
   FSRef pathFSRef;
   CFStringRef leafStrRef = nsnull;
@@ -475,7 +476,7 @@ NS_IMETHODIMP nsLocalFile::Create(PRUint32 type, PRUint32 permissions)
       break;
     ::CFStringGetCharacters(leafStrRef, CFRangeMake(0, leafLen), buffer.Elements());
     buffer[leafLen] = '\0';
-    nonExtantNodes.AppendString(nsString(nsDependentString(buffer.Elements())));
+    nonExtantNodes.AppendElement(nsString(nsDependentString(buffer.Elements())));
     ::CFRelease(leafStrRef);
     leafStrRef = nsnull;
     
@@ -493,14 +494,14 @@ NS_IMETHODIMP nsLocalFile::Create(PRUint32 type, PRUint32 permissions)
     ::CFRelease(leafStrRef);
   if (!success)
     return NS_ERROR_FAILURE;
-  PRInt32 nodesToCreate = nonExtantNodes.Count();
+  PRInt32 nodesToCreate = PRInt32(nonExtantNodes.Length());
   if (nodesToCreate == 0)
     return NS_ERROR_FILE_ALREADY_EXISTS;
   
   OSErr err;    
   nsAutoString nextNodeName;
   for (PRInt32 i = nodesToCreate - 1; i > 0; i--) {
-    nonExtantNodes.StringAt(i, nextNodeName);
+    nextNodeName = nonExtantNodes[i];
     err = ::FSCreateDirectoryUnicode(&pathFSRef,
                                       nextNodeName.Length(),
                                       (const UniChar *)nextNodeName.get(),
@@ -509,7 +510,7 @@ NS_IMETHODIMP nsLocalFile::Create(PRUint32 type, PRUint32 permissions)
     if (err != noErr)
       return MacErrorMapper(err);
   }
-  nonExtantNodes.StringAt(0, nextNodeName);
+  nextNodeName = nonExtantNodes[0];
   if (type == NORMAL_FILE_TYPE) {
     err = ::FSCreateFileUnicode(&pathFSRef,
                                 nextNodeName.Length(),