events: Get rid of GestureStatus in favour of EventResult.

ui/base/events/event_handler.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 UI_BASE_EVENTS_EVENT_HANDLER_H_
 #define UI_BASE_EVENTS_EVENT_HANDLER_H_
 
 #include <vector>
 
 #include "ui/base/events.h"
 #include "ui/base/ui_export.h"
 
 namespace ui {
 
 class GestureEvent;
 class KeyEvent;
 class MouseEvent;
 class ScrollEvent;
 class TouchEvent;
 
 class EventTarget;
 
-enum EventResult {
-  ER_UNHANDLED = 0,  // The event hasn't been handled. The event can be
-                     // propagated to other handlers.
-  ER_HANDLED,        // The event has already been handled, but it can still be
-                     // propagated to other handlers.
-  ER_CONSUMED,       // The event has been handled, and it should not be
-                     // propagated to other handlers.
-};
-
 // Dispatches events to appropriate targets.
 class UI_EXPORT EventHandler {
  public:
   EventHandler() {}
   virtual ~EventHandler() {}
 
   virtual EventResult OnKeyEvent(EventTarget* target,
                                  KeyEvent* event) = 0;
 
   virtual EventResult OnMouseEvent(EventTarget* target,
                                    MouseEvent* event) = 0;
 
   virtual EventResult OnScrollEvent(EventTarget* target,
                                     ScrollEvent* event) = 0;
 
   virtual TouchStatus OnTouchEvent(EventTarget* target,
                                    TouchEvent* event) = 0;
 
   virtual EventResult OnGestureEvent(EventTarget* target,
                                      GestureEvent* event) = 0;
 };
 
 typedef std::vector<EventHandler*> EventHandlerList;
 
 }  // namespace ui
 
 #endif  // UI_BASE_EVENTS_EVENT_HANDLER_H_