Android WebView: flush input events during onVSync

content/browser/renderer_host/render_widget_host_view_android.h

Index: content/browser/renderer_host/render_widget_host_view_android.h
diff --git a/content/browser/renderer_host/render_widget_host_view_android.h b/content/browser/renderer_host/render_widget_host_view_android.h
index 91f9d483731a958e316bb66a69f8ccea1c5f0e67..6190d5f7435e1758053a33e3ad7f6f06d7484b05 100644
--- a/content/browser/renderer_host/render_widget_host_view_android.h
+++ b/content/browser/renderer_host/render_widget_host_view_android.h
@@ -247,6 +247,8 @@ class CONTENT_EXPORT RenderWidgetHostViewAndroid
       const TextSurroundingSelectionCallback& callback);
 
  private:
+  enum VSyncSubscriberType { INPUT = 1 << 0, BEGIN_FRAME = 1 << 1 };

[boliu, 2014/08/20 20:30:00]

nit: separate lines (unless this is what clang-format did..?)

+
   // TouchSelectionControllerClient implementation.
   virtual bool SupportsAnimation() const OVERRIDE;
   virtual void SetNeedsAnimate() OVERRIDE;
@@ -317,12 +319,14 @@ class CONTENT_EXPORT RenderWidgetHostViewAndroid
 
   float GetDpiScale() const;
 
+  // type is a bit field containing one or more VSyncSubscriberType.
+  void SubscribeToVSync(uint32 type);
+  void UnsubscribeToVSync(uint32 type);
+  bool IsSubscribedToType(uint32 type);
+
   // The model object.
   RenderWidgetHostImpl* host_;
 
-  // Used to track whether this render widget needs a BeginFrame.
-  bool needs_begin_frame_;
-
   bool is_showing_;
 
   // ContentViewCoreImpl is our interface to the view system.
@@ -370,8 +374,6 @@ class CONTENT_EXPORT RenderWidgetHostViewAndroid
   bool touch_scrolling_;
   size_t potentially_active_fling_count_;
 
-  bool flush_input_requested_;
-
   int accelerated_surface_route_id_;
 
   // Size to use if we have no backing ContentViewCore
@@ -379,10 +381,13 @@ class CONTENT_EXPORT RenderWidgetHostViewAndroid
 
   const bool using_synchronous_compositor_;
 
+  // Used to track how VSync should be dispatched. For example, if this bit
+  // mask has BEGIN_FRAME bit on, a new frame will be requested during OnVSync.
+  uint32 vsync_subscribers_bitmask_;
+
   scoped_ptr<DelegatedFrameEvictor> frame_evictor_;
 
   size_t locks_on_frame_count_;
-  bool observing_root_window_;
 
   struct LastFrameInfo {
     LastFrameInfo(uint32 output_id,