Don't send touch move to renderer while scrolling

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 7d623442936ac33e5d9c92935bd9767a5efb3863..b825c43b281bd8f999c82c110d3d05774712505d 100644
--- a/content/browser/renderer_host/input/touch_event_queue.h
+++ b/content/browser/renderer_host/input/touch_event_queue.h
@@ -51,6 +51,14 @@ class TouchEventQueue {
   // additional queued touch-events to the renderer.
   void ProcessTouchAck(InputEventAckState ack_result);
 
+  // When scroll starts, we stop forwarding touch events to renderer. When
+  // scroll ends, we flush the queue and send touch end to renderer to release
+  // all existing touches. And we don't want to process the touch end in view,
+  // so we also clear the queue to not process the ack to the touch end.

[sadrul, 2013/08/06 19:34:19]

I think with this patchset, the sequence of events is:
 1. Browser queues up a bunch of events in the queue.
 2. Renderer doesn't prevent-default the touches.
 3. Browser starts sending gesture-scroll events.
 4. The RWHView implementations directly process the subsequent touch-events to
generate more scroll events.
 5. Scroll ends. At this point, the queued touch-move events upto step 3 are
sent to the RWHView. The touch-event is sent to the renderer.

Is this correct? If so, then this is buggy. The events queued up until step 3
needs to be processed by the RWHV before any of the subsequent touches.

+  void OnGestureScrollEnd();
+
+  void ClearQueue();
+
   // Empties the queue of touch events. This may result in any number of gesture
   // events being sent to the renderer.
   void FlushQueue();
@@ -78,6 +86,8 @@ class TouchEventQueue {
   typedef std::deque<CoalescedWebTouchEvent*> TouchQueue;
   TouchQueue touch_queue_;
 
+  TouchEventWithLatencyInfo latest_event_;
+
   // Maintain the ACK status for each touch point.
   typedef std::map<int, InputEventAckState> TouchPointAckStates;
   TouchPointAckStates touch_ack_states_;