[VSync Queue] Flush input in CommitComplete()

cc/trees/layer_tree_host_impl.h

Index: cc/trees/layer_tree_host_impl.h
diff --git a/cc/trees/layer_tree_host_impl.h b/cc/trees/layer_tree_host_impl.h
index e7b3f6163470bba5d7a5c42a1c31a8cacdb2c698..7f63660e74ce7e6d2864a9ef3fc07dcdaedbe740 100644
--- a/cc/trees/layer_tree_host_impl.h
+++ b/cc/trees/layer_tree_host_impl.h
@@ -154,6 +154,7 @@ class CC_EXPORT LayerTreeHostImpl
   // InputHandler implementation
   void BindToClient(InputHandlerClient* client,
                     bool wheel_scroll_latching_enabled) override;
+  InputHandlerState GetInputHandlerState() const override;
   InputHandler::ScrollStatus ScrollBegin(
       ScrollState* scroll_state,
       InputHandler::ScrollInputType type) override;
@@ -870,6 +871,8 @@ class CC_EXPORT LayerTreeHostImpl
 
   bool touchpad_and_wheel_scroll_latching_enabled_;
 
+  InputHandlerState input_handler_state_;
+
   DISALLOW_COPY_AND_ASSIGN(LayerTreeHostImpl);
 };