Revert of Refactoring button field and its type

third_party/WebKit/Source/core/events/MouseEvent.h

 /*
  * Copyright (C) 2001 Peter Kelly (pmk@post.com)
  * Copyright (C) 2001 Tobias Anton (anton@stud.fbi.fh-darmstadt.de)
  * Copyright (C) 2006 Samuel Weinig (sam.weinig@gmail.com)
  * Copyright (C) 2003, 2004, 2005, 2006, 2008 Apple Inc. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
@@ skipping 43 matching lines @@
 
     static MouseEvent* create(const AtomicString& eventType, AbstractView*, const PlatformMouseEvent&, int detail, Node* relatedTarget);
 
     static MouseEvent* create(ScriptState*, const AtomicString& eventType, const MouseEventInit&);
 
     static MouseEvent* create(const AtomicString& eventType, AbstractView*, Event* underlyingEvent, SimulatedClickCreationScope);
 
     ~MouseEvent() override;
 
     static unsigned short platformModifiersToButtons(unsigned modifiers);
+    static unsigned short buttonToButtons(short button);
 
     void initMouseEvent(ScriptState*, const AtomicString& type, bool canBubble, bool cancelable, AbstractView*,
         int detail, int screenX, int screenY, int clientX, int clientY,
         bool ctrlKey, bool altKey, bool shiftKey, bool metaKey,
         short button, EventTarget* relatedTarget, unsigned short buttons = 0);
 
     // WinIE uses 1,4,2 for left/middle/right but not for click (just for mousedown/up, maybe others),
     // but we will match the standard DOM.
     virtual short button() const { return m_button == -1 ? 0 : m_button; }
     unsigned short buttons() const { return m_buttons; }
@@ skipping 66 matching lines @@
     MouseEvent& event() const;
 
     DispatchEventResult dispatchEvent(EventDispatcher&) const override;
 };
 
 DEFINE_EVENT_TYPE_CASTS(MouseEvent);
 
 } // namespace blink
 
 #endif // MouseEvent_h