Move ash/system/web_notification message_center to ui/

ash/system/web_notification/web_notification.h

-// Copyright (c) 2012 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 ASH_SYSTEM_WEB_NOTIFICATION_WEB_NOTIFICATION_H_
-#define ASH_SYSTEM_WEB_NOTIFICATION_WEB_NOTIFICATION_H_
-
-#include <string>
-
-#include "base/string16.h"
-#include "ui/gfx/image/image_skia.h"
-
-namespace message_center {
-
-struct WebNotification {
-  WebNotification();
-  virtual ~WebNotification();
-
-  std::string id;
-  string16 title;
-  string16 message;
-  string16 display_source;
-  std::string extension_id;
-  gfx::ImageSkia image;
-  bool is_read;  // True if this has been seen in the message center
-  bool shown_as_popup;  // True if this has been shown as a popup notification
-};
-
-}  // namespace message_center
-
-#endif // ASH_SYSTEM_WEB_NOTIFICATION_WEB_NOTIFICATION_H_