Store the id of a contributing motion event in GestureEventData

ui/events/gesture_detection/gesture_event_data.h

Index: ui/events/gesture_detection/gesture_event_data.h
diff --git a/ui/events/gesture_detection/gesture_event_data.h b/ui/events/gesture_detection/gesture_event_data.h
index 280103a921b4c9c5cc16e30384b7a1bb1ac9eb99..f7f57a8b7defb37921059aaa58d3caae82c43ad3 100644
--- a/ui/events/gesture_detection/gesture_event_data.h
+++ b/ui/events/gesture_detection/gesture_event_data.h
@@ -16,17 +16,20 @@ class GestureEventDataPacket;
 
 struct GESTURE_DETECTION_EXPORT GestureEventData {
   GestureEventData(EventType type,
+                   int motion_event_id,
                    base::TimeTicks time,
                    float x,
                    float y,
                    const GestureEventDetails& details);
 
   GestureEventData(EventType type,
+                   int motion_event_id,
                    base::TimeTicks time,
                    float x,
                    float y);
 
   EventType type;
+  int motion_event_id;
   base::TimeTicks time;
   float x;
   float y;