Mark touchcancel events as uncancelable

content/browser/renderer_host/input/web_touch_event_traits.cc

-// Copyright 2014 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/browser/renderer_host/input/web_touch_event_traits.h"
-
-#include "base/logging.h"
-
-using blink::WebInputEvent;
-using blink::WebTouchEvent;
-
-namespace content {
-
-namespace {
-
-bool AllTouchPointsHaveState(const WebTouchEvent& event,
-                             blink::WebTouchPoint::State state) {
-  if(!event.touchesLength)
-    return false;
-  for (size_t i = 0; i < event.touchesLength; ++i) {
-    if (event.touches[i].state != state)
-      return false;
-  }
-  return true;
-}
-
-}  // namespace
-
-bool WebTouchEventTraits::IsTouchSequenceStart(const WebTouchEvent& event) {
-  DCHECK(event.touchesLength);
-  if (event.type != WebInputEvent::TouchStart)
-    return false;
-  return AllTouchPointsHaveState(event, blink::WebTouchPoint::StatePressed);
-}
-
-}  // namespace content