Bug 1041751 - Do not create an empty APZ test data bucket for each paint when APZ test logging is not pref'd on. r=kats

gfx/layers/client/ClientLayerManager.cpp

@@ -28,6 +28,7 @@
 #include "nsXULAppAPI.h"                // for XRE_GetProcessType, etc
 #include "TiledLayerBuffer.h"
 #include "mozilla/dom/WindowBinding.h"  // for Overfill Callback
+#include "gfxPrefs.h"
 #ifdef MOZ_WIDGET_ANDROID
 #include "AndroidBridge.h"
 #endif
@@ -167,7 +168,9 @@ ClientLayerManager::BeginTransactionWithTarget(gfxContext* aTarget)
   // If this is a new paint, increment the paint sequence number.
   if (!mIsRepeatTransaction) {
     ++mPaintSequenceNumber;
-    mApzTestData.StartNewPaint(mPaintSequenceNumber);
+    if (gfxPrefs::APZTestLoggingEnabled()) {
+      mApzTestData.StartNewPaint(mPaintSequenceNumber);
+    }
   }
 }
 
@@ -324,6 +327,14 @@ ClientLayerManager::GetCompositorSideAPZTestData(APZTestData* aData) const
   }
 }
 
+void
+ClientLayerManager::StartNewRepaintRequest(SequenceNumber aSequenceNumber)
+{
+  if (gfxPrefs::APZTestLoggingEnabled()) {
+    mApzTestData.StartNewRepaintRequest(aSequenceNumber);
+  }
+}
+
 bool
 ClientLayerManager::RequestOverfill(mozilla::dom::OverfillCallback* aCallback)
 {

gfx/layers/client/ClientLayerManager.h

@@ -203,10 +203,8 @@ public:
   // Log APZ test data for a repaint request. The sequence number must be
   // passed in from outside, and APZTestData::StartNewRepaintRequest() needs
   // to be called from the outside as well when a new repaint request is started.
-  void StartNewRepaintRequest(SequenceNumber aSequenceNumber)
-  {
-    mApzTestData.StartNewRepaintRequest(aSequenceNumber);
-  }
+  void StartNewRepaintRequest(SequenceNumber aSequenceNumber);
+
   // TODO(botond): When we start using this and write a wrapper similar to
   // nsLayoutUtils::LogTestDataForPaint(), make sure that wrapper checks
   // gfxPrefs::APZTestLoggingEnabled().