Send touch cancel to renderer when scrolling starts

content/browser/renderer_host/input/touch_event_queue.h

Index: content/browser/renderer_host/input/touch_event_queue.h
diff --git a/content/browser/renderer_host/input/touch_event_queue.h b/content/browser/renderer_host/input/touch_event_queue.h
index 358fae9c50d8d50f4cf227992c4c0c07341ca09d..0d8dd758e7927883515f538015b7c4066efab099 100644
--- a/content/browser/renderer_host/input/touch_event_queue.h
+++ b/content/browser/renderer_host/input/touch_event_queue.h
@@ -52,6 +52,8 @@ class TouchEventQueue {
   void ProcessTouchAck(InputEventAckState ack_result,
                        const ui::LatencyInfo& latency_info);
 
+  void OnGestureScrollEvent(const GestureEventWithLatencyInfo& gesture_event);
+
   // Empties the queue of touch events. This may result in any number of gesture
   // events being sent to the renderer.
   void FlushQueue();
@@ -61,10 +63,6 @@ class TouchEventQueue {
     return touch_queue_.empty();
   }
 
-  void set_no_touch_move_to_renderer(bool value) {
-    no_touch_move_to_renderer_ = value;
-  }
-
  private:
   friend class MockRenderWidgetHost;
   friend class ImmediateInputRouterTest;
@@ -92,10 +90,17 @@ class TouchEventQueue {
   // Used to defer touch forwarding when ack dispatch triggers |QueueEvent()|.
   bool dispatching_touch_ack_;
 
-  // Don't send touch move events to renderer. This is enabled when the page
-  // is scrolling. This behaviour is currently enabled only on aura behind a
-  // flag.
-  bool no_touch_move_to_renderer_;
+  // Don't send touch events to renderer. This is enabled when the page
+  // is scrolling. This behaviour is currently enabled only on aura behind
+  // a flag.
+  bool no_touch_to_renderer_;
+
+  // Latest event that is queued.
+  TouchEventWithLatencyInfo latest_event_;

[sadrul, 2013/09/23 16:17:33]

Why do you need this?

+
+  // When scroll begins, we send the |synthesized_cancel_event_| to renderer
+  // and when it is acked back we drop it before forwarding it to view.
+  CoalescedWebTouchEvent* synthesized_cancel_event_;

[sadrul, 2013/09/23 16:17:33]

We shouldn't hold onto a raw pointer like this. Add some attribute on
CoalescedWebTouchEvent that carries this information instead.

 
   DISALLOW_COPY_AND_ASSIGN(TouchEventQueue);
 };