Removed |which| from KeyboardEvent and MouseEvent.

third_party/WebKit/Source/core/events/UIEvent.cpp

 /*
  * 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, 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 72 matching lines @@
 }
 
 bool UIEvent::IsUIEvent() const {
   return true;
 }
 
 const AtomicString& UIEvent::InterfaceName() const {
   return EventNames::UIEvent;
 }
 
-int UIEvent::which() const {
+unsigned UIEvent::which() const {
   return 0;
 }
 
 DEFINE_TRACE(UIEvent) {
   visitor->Trace(view_);
   visitor->Trace(source_capabilities_);
   Event::Trace(visitor);
 }
 
 }  // namespace blink