Fix movementX/Y attributes for touch pointer events

ui/events/blink/blink_event_util.cc

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // MSVC++ requires this to be set before any other includes to get M_PI.
 #define _USE_MATH_DEFINES
 
 #include "ui/events/blink/blink_event_util.h"
 
 #include <stddef.h>
@@ skipping 315 matching lines @@
   // The WebTouchPoints include absolute position information. So it is
   // sufficient to simply replace the previous event with the new event->
   // However, it is necessary to make sure that all the points have the
   // correct state, i.e. the touch-points that moved in the last event, but
   // didn't change in the current event, will have Stationary state. It is
   // necessary to change them back to Moved state.
   WebTouchEvent old_event = *event;
   *event = event_to_coalesce;
   for (unsigned i = 0; i < event->touchesLength; ++i) {
     int i_old = GetIndexOfTouchID(old_event, event->touches[i].id);
-    if (old_event.touches[i_old].state == blink::WebTouchPoint::StateMoved)
+    if (old_event.touches[i_old].state == blink::WebTouchPoint::StateMoved) {
       event->touches[i].state = blink::WebTouchPoint::StateMoved;
+      event->touches[i].movementX += old_event.touches[i_old].movementX;
+      event->touches[i].movementY += old_event.touches[i_old].movementY;
+    }

[sadrul, 2017/02/07 03:48:30]

Mind adding a test for this in blink_event_util_unittest.cc?

[Navid Zolghadr, 2017/02/08 17:18:49]

Done.

   }
   event->movedBeyondSlopRegion |= old_event.movedBeyondSlopRegion;
   event->dispatchType = MergeDispatchTypes(old_event.dispatchType,
                                            event_to_coalesce.dispatchType);
 }
 
 bool CanCoalesce(const WebGestureEvent& event_to_coalesce,
                  const WebGestureEvent& event) {
   if (event.type() != event_to_coalesce.type() ||
       event.sourceDevice != event_to_coalesce.sourceDevice ||
@@ skipping 613 matching lines @@
   switch (type) {
     case blink::WebGestureEvent::GestureScrollUpdate:
     case blink::WebGestureEvent::GesturePinchUpdate:
       return true;
     default:
       return false;
   }
 }
 
 }  // namespace ui