Provide a vsync notification to the renderer

content/browser/renderer_host/render_widget_host_impl.h

Index: content/browser/renderer_host/render_widget_host_impl.h
diff --git a/content/browser/renderer_host/render_widget_host_impl.h b/content/browser/renderer_host/render_widget_host_impl.h
index bd228ac9fc36ae0c79e185a36c93ccf08a357b7f..a849cbb94cf6a34a23a1ffd6f00c144353223da7 100644
--- a/content/browser/renderer_host/render_widget_host_impl.h
+++ b/content/browser/renderer_host/render_widget_host_impl.h
@@ -382,6 +382,10 @@ class CONTENT_EXPORT RenderWidgetHostImpl : virtual public RenderWidgetHost,
   virtual void UpdateVSyncParameters(base::TimeTicks timebase,
                                      base::TimeDelta interval);
 
+  // Notifies the RenderWidget that the display vsync signal was triggered and
+  // now is a good time to render a new frame.
+  virtual void SendVSync(base::TimeTicks frame_time);
+
   // Called by the view in response to AcceleratedSurfaceBuffersSwapped or
   // AcceleratedSurfacePostSubBuffer.
   static void AcknowledgeBufferPresent(
@@ -555,6 +559,7 @@ class CONTENT_EXPORT RenderWidgetHostImpl : virtual public RenderWidgetHost,
                                          const gfx::Size& size,
                                          int32 gpu_process_host_id);
   void OnSwapCompositorFrame(const cc::CompositorFrame& frame);
+  void OnEnableVSyncNotification(bool enable);
   void OnUpdateRect(const ViewHostMsg_UpdateRect_Params& params);
   void OnUpdateIsDelayed();
   void OnInputEventAck(WebKit::WebInputEvent::Type event_type,