cc: Delay start of scrollbar animation setNeedsRedraw.

cc/thread_proxy.h

Index: cc/thread_proxy.h
diff --git a/cc/thread_proxy.h b/cc/thread_proxy.h
index a56b5bede54347ef6be9afc1c8db1e2a393250a9..e9af5a0d7e42b469c977b30bc07a208c23bfb630 100644
--- a/cc/thread_proxy.h
+++ b/cc/thread_proxy.h
@@ -74,6 +74,7 @@ public:
     virtual void SendManagedMemoryStats() OVERRIDE;
     virtual bool IsInsideDraw() OVERRIDE;
     virtual void RenewTreePriority() OVERRIDE;
+    virtual void RequestScrollbarAnimationOnImplThread(double delay) OVERRIDE;
 
     // SchedulerClient implementation
     virtual void scheduledActionBeginFrame() OVERRIDE;
@@ -149,6 +150,7 @@ private:
     void asValueOnImplThread(CompletionEvent*, base::DictionaryValue*) const;
     void renewTreePriorityOnImplThread();
     void didSwapUseIncompleteTileOnImplThread();
+    void StartScrollbarAnimationOnImplThread();
 
     // Accessed on main thread only.
     bool m_animateRequested; // Set only when setNeedsAnimate is called.