Send vsync notification from browser to renderer

content/port/browser/render_widget_host_view_port.h

Index: content/port/browser/render_widget_host_view_port.h
diff --git a/content/port/browser/render_widget_host_view_port.h b/content/port/browser/render_widget_host_view_port.h
index 397d71d3c3e865bf35b3edb033fa9de963428f6b..7043b7306b2006caf244df3b8150d3bec7d5af96 100644
--- a/content/port/browser/render_widget_host_view_port.h
+++ b/content/port/browser/render_widget_host_view_port.h
@@ -225,6 +225,10 @@ class CONTENT_EXPORT RenderWidgetHostViewPort : public RenderWidgetHostView,
       const GpuHostMsg_AcceleratedSurfacePostSubBuffer_Params& params_in_pixel,
       int gpu_host_id) = 0;
 
+  // Request a periodic vsync signal notification from the View. The signal will
+  // be delivered until explicitly disabled.
+  virtual void EnableVSyncNotification(bool enable) = 0;
+
   // Release the accelerated surface temporarily. It will be recreated on the
   // next swap buffers or post sub buffer.
   virtual void AcceleratedSurfaceSuspend() = 0;