Manage RequestAnimationFrameCallbacks with OwnPtrs instead of RefPtrs

Source/core/dom/ScriptedAnimationController.h

Index: Source/core/dom/ScriptedAnimationController.h
diff --git a/Source/core/dom/ScriptedAnimationController.h b/Source/core/dom/ScriptedAnimationController.h
index 7c83094406d09625486bb0e4c71247f141482873..5f7efb887e9cc96ebe8810b48d59ff1d548bc853 100644
--- a/Source/core/dom/ScriptedAnimationController.h
+++ b/Source/core/dom/ScriptedAnimationController.h
@@ -50,7 +50,7 @@ public:
 
     typedef int CallbackId;
 
-    int registerCallback(PassRefPtr<RequestAnimationFrameCallback>);
+    int registerCallback(PassOwnPtr<RequestAnimationFrameCallback>);
     void cancelCallback(CallbackId);
     void serviceScriptedAnimations(double monotonicTimeNow);
 
@@ -68,8 +68,9 @@ private:
     void dispatchEvents();
     void executeCallbacks(double monotonicTimeNow);
 
-    typedef Vector<RefPtr<RequestAnimationFrameCallback> > CallbackList;
+    typedef Vector<OwnPtr<RequestAnimationFrameCallback> > CallbackList;
     CallbackList m_callbacks;
+    CallbackList m_callbacksToInvoke; // only non-empty while inside executeCallbacks
 
     Document* m_document;
     CallbackId m_nextCallbackId;