[VSync Queue] Plug touch ack to gesture events and flush vsync queue if necessary

third_party/WebKit/public/platform/WebGestureEvent.h

Index: third_party/WebKit/public/platform/WebGestureEvent.h
diff --git a/third_party/WebKit/public/platform/WebGestureEvent.h b/third_party/WebKit/public/platform/WebGestureEvent.h
index 4cefc3414fbff56fd901ad0531a5c6027fcf9ee3..94d56575b0612378ded98ae89cf2e75763b73e5c 100644
--- a/third_party/WebKit/public/platform/WebGestureEvent.h
+++ b/third_party/WebKit/public/platform/WebGestureEvent.h
@@ -37,6 +37,7 @@ class WebGestureEvent : public WebInputEvent {
   int global_x;
   int global_y;
   WebGestureDevice source_device;
+  bool is_source_touch_event_set_non_blocking;

[pfeldman, 2017/06/09 18:38:08]

Are you relying upon all the call sites to initialize these? Looks like an
anti-pattern to me.

[chongz, 2017/06/09 18:58:58]

Done. Thanks for catching! Yes it would be safer to initialize it in ctors.

 
   // If the WebGestureEvent has sourceDevice=WebGestureDeviceTouchscreen, this
   // field contains the unique identifier for the touch event that released