Set the unique_event_id when converting from TouchEvent to WebTouchEvent

ui/events/gestures/motion_event_aura.cc

Index: ui/events/gestures/motion_event_aura.cc
diff --git a/ui/events/gestures/motion_event_aura.cc b/ui/events/gestures/motion_event_aura.cc
index 174918fedc5a545da380fd2efd3205e36c3e3258..01df3f6042620f5dd945e786f91d93affda7a1db 100644
--- a/ui/events/gestures/motion_event_aura.cc
+++ b/ui/events/gestures/motion_event_aura.cc
@@ -125,15 +125,12 @@ bool MotionEventAura::OnTouch(const TouchEvent& touch) {
   }
 
   UpdateCachedAction(touch);
+  set_unique_event_id(touch.unique_event_id());
   set_flags(touch.flags());
   set_event_time(touch.time_stamp() + base::TimeTicks());
   return true;
 }
 
-int MotionEventAura::GetId() const {
-  return GetPointerId(0);
-}
-
 void MotionEventAura::CleanupRemovedTouchPoints(const TouchEvent& event) {
   if (event.type() != ET_TOUCH_RELEASED &&
       event.type() != ET_TOUCH_CANCELLED) {