Revert of Move Event to oilpan's heap

Source/core/events/Event.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, 2007, 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 28 matching lines @@
 
 struct EventInit {
     STACK_ALLOCATED();
 public:
     EventInit();
 
     bool bubbles;
     bool cancelable;
 };
 
-class Event : public RefCountedWillBeRefCountedGarbageCollected<Event>,  public ScriptWrappable {
+class Event : public RefCounted<Event>,  public ScriptWrappable {
 public:
     enum PhaseType {
         NONE                = 0,
         CAPTURING_PHASE     = 1,
         AT_TARGET           = 2,
         BUBBLING_PHASE      = 3
     };
 
     enum EventType {
         MOUSEDOWN           = 1,
@@ skipping 149 matching lines @@
     RefPtr<Event> m_underlyingEvent;
     OwnPtr<EventPath> m_eventPath;
 };
 
 #define DEFINE_EVENT_TYPE_CASTS(typeName) \
     DEFINE_TYPE_CASTS(typeName, Event, event, event->is##typeName(), event.is##typeName())
 
 } // namespace WebCore
 
 #endif // Event_h