Bug 1155477 - Convert nsINode::Slots::mChildNodes to an nsRefPtr; r=baku

MSVC 7 is no longer supported, so this can now be an nsRefPtr.

dom/base/FragmentOrElement.h

@@ -17,7 +17,6 @@
 #include "nsAttrAndChildArray.h"          // member
 #include "nsCycleCollectionParticipant.h" // NS_DECL_CYCLE_*
 #include "nsIContent.h"                   // base class
-#include "nsINodeList.h"                  // base class
 #include "nsIWeakReference.h"             // base class
 #include "nsNodeUtils.h"                  // class member nsNodeUtils::CloneNodeImpl
 #include "nsIHTMLCollection.h"
@@ -38,50 +37,6 @@ class Element;
 }
 }
 
-/**
- * Class that implements the nsIDOMNodeList interface (a list of children of
- * the content), by holding a reference to the content and delegating GetLength
- * and Item to its existing child list.
- * @see nsIDOMNodeList
- */
-class nsChildContentList final : public nsINodeList
-{
-public:
-  explicit nsChildContentList(nsINode* aNode)
-    : mNode(aNode)
-  {
-  }
-
-  NS_DECL_CYCLE_COLLECTING_ISUPPORTS
-  NS_DECL_CYCLE_COLLECTION_SKIPPABLE_SCRIPT_HOLDER_CLASS(nsChildContentList)
-
-  // nsWrapperCache
-  virtual JSObject* WrapObject(JSContext *cx, JS::Handle<JSObject*> aGivenProto) override;
-
-  // nsIDOMNodeList interface
-  NS_DECL_NSIDOMNODELIST
-
-  // nsINodeList interface
-  virtual int32_t IndexOf(nsIContent* aContent) override;
-  virtual nsIContent* Item(uint32_t aIndex) override;
-
-  void DropReference()
-  {
-    mNode = nullptr;
-  }
-
-  virtual nsINode* GetParentObject() override
-  {
-    return mNode;
-  }
-
-private:
-  ~nsChildContentList() {}
-
-  // The node whose children make up the list (weak reference)
-  nsINode* mNode;
-};
-
 /**
  * A class that implements nsIWeakReference
  */

dom/base/nsINode.cpp

@@ -113,7 +113,6 @@ nsINode::nsSlots::~nsSlots()
 {
   if (mChildNodes) {
     mChildNodes->DropReference();
-    NS_RELEASE(mChildNodes);
   }
 
   if (mWeakReference) {
@@ -133,7 +132,6 @@ nsINode::nsSlots::Unlink()
 {
   if (mChildNodes) {
     mChildNodes->DropReference();
-    NS_RELEASE(mChildNodes);
   }
 }
 
@@ -369,12 +367,8 @@ nsINodeList*
 nsINode::ChildNodes()
 {
   nsSlots* slots = Slots();
-  if (!slots->mChildNodes) {
-    slots->mChildNodes = new nsChildContentList(this);
-    if (slots->mChildNodes) {
-      NS_ADDREF(slots->mChildNodes);
-    }
-  }
+  MOZ_ASSERT(!slots->mChildNodes);
+  slots->mChildNodes = new nsChildContentList(this);
 
   return slots->mChildNodes;
 }

dom/base/nsINode.h

@@ -11,6 +11,7 @@
 #include "nsGkAtoms.h"              // for nsGkAtoms::baseURIProperty
 #include "nsIDOMNode.h"
 #include "mozilla/dom/NodeInfo.h"            // member (in nsCOMPtr)
+#include "nsINodeList.h"            // base class
 #include "nsIVariant.h"             // for use in GetUserData()
 #include "nsNodeInfoManager.h"      // for use in NodePrincipal()
 #include "nsPropertyTable.h"        // for typedefs
@@ -41,7 +42,7 @@ class nsIDOMNodeList;
 class nsIEditor;
 class nsIFrame;
 class nsIMutationObserver;
-class nsINodeList;
+class nsINode;
 class nsIPresShell;
 class nsIPrincipal;
 class nsIURI;
@@ -234,6 +235,50 @@ private:
   static uint64_t sGeneration;
 };
 
+/**
+ * Class that implements the nsIDOMNodeList interface (a list of children of
+ * the content), by holding a reference to the content and delegating GetLength
+ * and Item to its existing child list.
+ * @see nsIDOMNodeList
+ */
+class nsChildContentList final : public nsINodeList
+{
+public:
+  explicit nsChildContentList(nsINode* aNode)
+    : mNode(aNode)
+  {
+  }
+
+  NS_DECL_CYCLE_COLLECTING_ISUPPORTS
+  NS_DECL_CYCLE_COLLECTION_SKIPPABLE_SCRIPT_HOLDER_CLASS(nsChildContentList)
+
+  // nsWrapperCache
+  virtual JSObject* WrapObject(JSContext *cx, JS::Handle<JSObject*> aGivenProto) override;
+
+  // nsIDOMNodeList interface
+  NS_DECL_NSIDOMNODELIST
+
+  // nsINodeList interface
+  virtual int32_t IndexOf(nsIContent* aContent) override;
+  virtual nsIContent* Item(uint32_t aIndex) override;
+
+  void DropReference()
+  {
+    mNode = nullptr;
+  }
+
+  virtual nsINode* GetParentObject() override
+  {
+    return mNode;
+  }
+
+private:
+  ~nsChildContentList() {}
+
+  // The node whose children make up the list (weak reference)
+  nsINode* mNode;
+};
+
 // This should be used for any nsINode sub-class that has fields of its own
 // that it needs to measure;  any sub-class that doesn't use it will inherit
 // SizeOfExcludingThis from its super-class.  SizeOfIncludingThis() need not be
@@ -1021,8 +1066,7 @@ public:
   {
   public:
     nsSlots()
-      : mChildNodes(nullptr),
-        mWeakReference(nullptr)
+      : mWeakReference(nullptr)
     {
     }
 
@@ -1042,10 +1086,8 @@ public:
      * An object implementing nsIDOMNodeList for this content (childNodes)
      * @see nsIDOMNodeList
      * @see nsGenericHTMLElement::GetChildNodes
-     *
-     * MSVC 7 doesn't like this as an nsRefPtr
      */
-    nsChildContentList* mChildNodes;
+    nsRefPtr<nsChildContentList> mChildNodes;
 
     /**
      * Weak reference to this node.  This is cleared by the destructor of

dom/base/nsINodeList.h

@@ -8,13 +8,15 @@
 
 #include "nsIDOMNodeList.h"
 #include "nsWrapperCache.h"
-#include "nsIContent.h"
 
 // IID for the nsINodeList interface
 #define NS_INODELIST_IID \
 { 0xadb5e54c, 0x6e96, 0x4102, \
  { 0x8d, 0x40, 0xe0, 0x12, 0x3d, 0xcf, 0x48, 0x7a } }
 
+class nsIContent;
+class nsINode;
+
 /**
  * An internal interface for a reasonably fast indexOf.
  */