bug 679786 - telemetry reporting use of ISimpleDOM* interfaces r=surkov

accessible/src/base/Statistics.h

@@ -49,6 +49,12 @@ namespace statistics {
   inline void A11yInitialized()
     { Telemetry::Accumulate(Telemetry::A11Y_INSTANTIATED, true); }
 
+  /**
+   * Report that ISimpleDOM* has been used.
+   */
+  inline void ISimpleDOMUsed()
+    { Telemetry::Accumulate(Telemetry::ISIMPLE_DOM_USAGE, 1); }
+
 } // namespace statistics
 } // namespace a11y
 } // namespace mozilla

accessible/src/msaa/nsAccessNodeWrap.cpp

@@ -46,6 +46,7 @@
 #include "nsCoreUtils.h"
 #include "nsRootAccessible.h"
 #include "nsWinUtils.h"
+#include "Statistics.h"
 
 #include "nsAttrName.h"
 #include "nsIDocument.h"
@@ -59,6 +60,7 @@
 #include "mozilla/Preferences.h"
 
 using namespace mozilla;
+using namespace mozilla::a11y;
 
 /// the accessible library and cached methods
 HINSTANCE nsAccessNodeWrap::gmAccLib = nsnull;
@@ -120,11 +122,14 @@ STDMETHODIMP nsAccessNodeWrap::QueryInterface(REFIID iid, void** ppv)
 {
   *ppv = nsnull;
 
-  if (IID_IUnknown == iid || IID_ISimpleDOMNode == iid)
+  if (IID_IUnknown == iid) {
     *ppv = static_cast<ISimpleDOMNode*>(this);
-
-  if (nsnull == *ppv)
+  } else if (IID_ISimpleDOMNode == iid) {
+    statistics::ISimpleDOMUsed();
+    *ppv = static_cast<ISimpleDOMNode*>(this);
+  } else {
     return E_NOINTERFACE;      //iid not supported.
+  }
    
   (reinterpret_cast<IUnknown*>(*ppv))->AddRef(); 
   return S_OK;

accessible/src/msaa/nsDocAccessibleWrap.cpp

@@ -43,6 +43,7 @@
 #include "nsIAccessibilityService.h"
 #include "nsRootAccessible.h"
 #include "nsWinUtils.h"
+#include "Statistics.h"
 
 #include "nsIDocShell.h"
 #include "nsIDocShellTreeNode.h"
@@ -54,6 +55,8 @@
 #include "nsIViewManager.h"
 #include "nsIWebNavigation.h"
 
+using namespace mozilla::a11y;
+
 /* For documentation of the accessibility architecture, 
  * see http://lxr.mozilla.org/seamonkey/source/accessible/accessible-docs.html
  */
@@ -91,12 +94,11 @@ STDMETHODIMP nsDocAccessibleWrap::QueryInterface(REFIID iid, void** ppv)
 {
   *ppv = NULL;
 
-  if (IID_ISimpleDOMDocument == iid)
-    *ppv = static_cast<ISimpleDOMDocument*>(this);
-
-  if (NULL == *ppv)
+  if (IID_ISimpleDOMDocument != iid)
     return nsHyperTextAccessibleWrap::QueryInterface(iid, ppv);
-    
+
+  statistics::ISimpleDOMUsed();
+  *ppv = static_cast<ISimpleDOMDocument*>(this);
   (reinterpret_cast<IUnknown*>(*ppv))->AddRef();
   return S_OK;
 }

accessible/src/msaa/nsTextAccessibleWrap.cpp

@@ -41,6 +41,7 @@
 
 #include "nsCoreUtils.h"
 #include "nsDocAccessible.h"
+#include "Statistics.h"
 #include "nsIFrame.h"
 #include "nsFontMetrics.h"
 #include "nsPresContext.h"
@@ -48,6 +49,8 @@
 
 #include "gfxFont.h"
 
+using namespace mozilla::a11y;
+
 ////////////////////////////////////////////////////////////////////////////////
 // nsTextAccessibleWrap Accessible
 ////////////////////////////////////////////////////////////////////////////////
@@ -72,11 +75,14 @@ STDMETHODIMP nsTextAccessibleWrap::QueryInterface(REFIID iid, void** ppv)
 {
   *ppv = nsnull;
 
-  if (IID_IUnknown == iid || IID_ISimpleDOMText == iid)
+  if (IID_IUnknown == iid) {
     *ppv = static_cast<ISimpleDOMText*>(this);
-
-  if (nsnull == *ppv)
+  } else if (IID_ISimpleDOMText == iid) {
+    statistics::ISimpleDOMUsed();
+    *ppv = static_cast<ISimpleDOMText*>(this);
+  } else {
     return nsAccessibleWrap::QueryInterface(iid, ppv);
+  }
    
   (reinterpret_cast<IUnknown*>(*ppv))->AddRef(); 
   return S_OK;

toolkit/components/telemetry/TelemetryHistograms.h

@@ -53,6 +53,7 @@
  * a11y telemetry
  */
 HISTOGRAM(A11Y_INSTANTIATED, 0, 1, 2, BOOLEAN, "has accessibility support been instantiated")
+HISTOGRAM(ISIMPLE_DOM_USAGE, 0, 1, 2, BOOLEAN, "have the ISimpleDOM* accessibility interfaces been used")
 
 HISTOGRAM(CYCLE_COLLECTOR, 1, 10000, 50, EXPONENTIAL, "Time spent on one cycle collection (ms)")
 HISTOGRAM(CYCLE_COLLECTOR_VISITED_REF_COUNTED, 1, 300000, 50, EXPONENTIAL, "Number of ref counted objects visited by the cycle collector")