Always reset touch action at the beginning of a new gesture sequence

content/common/input/web_input_event_traits.h

 // 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.
 
 #ifndef CONTENT_COMMON_INPUT_WEB_INPUT_EVENT_TRAITS_H_
 #define CONTENT_COMMON_INPUT_WEB_INPUT_EVENT_TRAITS_H_
 
 #include "base/basictypes.h"
 #include "content/common/input/scoped_web_input_event.h"
 #include "third_party/WebKit/public/web/WebInputEvent.h"
 
 namespace content {
 
 // Utility class for performing operations on and with WebInputEvents.
 class CONTENT_EXPORT WebInputEventTraits {
  public:
   static const char* GetName(blink::WebInputEvent::Type type);
   static size_t GetSize(blink::WebInputEvent::Type type);
   static ScopedWebInputEvent Clone(const blink::WebInputEvent& event);
   static void Delete(blink::WebInputEvent* event);
   static bool CanCoalesce(const blink::WebInputEvent& event_to_coalesce,
                           const blink::WebInputEvent& event);
   static void Coalesce(const blink::WebInputEvent& event_to_coalesce,
                        blink::WebInputEvent* event);
   static bool IgnoresAckDisposition(blink::WebInputEvent::Type type);
+  static bool IsNewTouchSequence(const blink::WebTouchEvent& event);

[jdduke (slow), 2014/02/21 15:45:33]

I wonder if it's worth having a WebTouchEventTraits in
content/renderer_host/input where we can add perhaps a few additional queries
(IsTouchSequenceEnd()? IsValidTouchEvent()?).  We could move it to common should
the need arise to use it elsewhere?

Also, we should be consistent with the GestureEventPacket naming here, e.g.,
TouchSequenceBegin, or NewTouchSequence, but not both... Perhaps a better name
is |TouchSequence{Start,End}| to parallel Touch{Start,End}.

[tdresser, 2014/02/21 19:14:03]

Done.

 };
 
 }  // namespace content
 
 #endif  // CONTENT_COMMON_INPUT_WEB_INPUT_EVENT_TRAITS_H_