Ignore TouchCancel ack dispositions

content/common/input/web_input_event_traits.cc

 // Copyright 2013 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.
 
 #include "content/common/input/web_input_event_traits.h"
 
 #include "base/logging.h"
 
 using blink::WebGestureEvent;
 using blink::WebInputEvent;
@@ skipping 267 matching lines @@
 }
 
 void WebInputEventTraits::Coalesce(const WebInputEvent& event_to_coalesce,
                                    WebInputEvent* event) {
   DCHECK(event);
   Apply(WebInputEventCoalesce(), event->type, event_to_coalesce, event);
 }
 
 bool WebInputEventTraits::IgnoresAckDisposition(
     blink::WebInputEvent::Type type) {
-  return type == WebInputEvent::GestureTapDown ||
-      type == WebInputEvent::GestureShowPress ||
-      type == WebInputEvent::GestureTapCancel ||
-      type == WebInputEvent::GesturePinchBegin ||
-      type == WebInputEvent::GesturePinchEnd ||
-      type == WebInputEvent::GestureScrollBegin ||
-      type == WebInputEvent::GestureScrollEnd;
+  switch (type) {
+    case WebInputEvent::GestureTapDown:
+    case WebInputEvent::GestureShowPress:
+    case WebInputEvent::GestureTapCancel:
+    case WebInputEvent::GesturePinchBegin:
+    case WebInputEvent::GesturePinchEnd:
+    case WebInputEvent::GestureScrollBegin:
+    case WebInputEvent::GestureScrollEnd:
+    case WebInputEvent::TouchCancel:
+      return true;
+    default:
+      break;
+  }
+  return false;
 }
 
 }  // namespace content