Move synthetic gesture input to be aligned with BeginFrame.

content/browser/renderer_host/render_widget_host_view_aura.h

Index: content/browser/renderer_host/render_widget_host_view_aura.h
diff --git a/content/browser/renderer_host/render_widget_host_view_aura.h b/content/browser/renderer_host/render_widget_host_view_aura.h
index 0c10ef0b8304b5a3b159ca8013bd2f445e678a7b..e641cf82344183771264efc1f659567cdf8f7aef 100644
--- a/content/browser/renderer_host/render_widget_host_view_aura.h
+++ b/content/browser/renderer_host/render_widget_host_view_aura.h
@@ -162,6 +162,7 @@ class CONTENT_EXPORT RenderWidgetHostViewAura
   void EndFrameSubscription() override;
   bool HasAcceleratedSurface(const gfx::Size& desired_size) override;
   gfx::Rect GetBoundsInRootWindow() override;
+  void OnSetNeedsFlushInput() override;
   void WheelEventAck(const blink::WebMouseWheelEvent& event,
                      InputEventAckState ack_result) override;
   void GestureEventAck(const blink::WebGestureEvent& event,
@@ -532,6 +533,7 @@ class CONTENT_EXPORT RenderWidgetHostViewAura
   // Forwards a mouse event to this view's parent window delegate.
   void ForwardMouseEventToParent(ui::MouseEvent* event);
 
+  // Adds/Removes frame observer based on state.
   void UpdateNeedsBeginFramesInternal();
 
   // Returns the RenderViewHostDelegateView instance for this view. Returns
@@ -598,6 +600,9 @@ class CONTENT_EXPORT RenderWidgetHostViewAura
   // Whether a request for begin frames has been issued.
   bool needs_begin_frames_;
 
+  // Whether a request to flush input has been issued.
+  bool needs_flush_input_;
+
   // Whether or not a frame observer has been added.
   bool added_frame_observer_;