Oilpan: Replace most of RefPtrs for Event objects with oilpan's transition types

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 154 matching lines @@
     }
     void setDefaultPrevented(bool defaultPrevented) { m_defaultPrevented = defaultPrevented; }
 
     bool defaultHandled() const { return m_defaultHandled; }
     void setDefaultHandled() { m_defaultHandled = true; }
 
     bool cancelBubble() const { return m_cancelBubble; }
     void setCancelBubble(bool cancel) { m_cancelBubble = cancel; }
 
     Event* underlyingEvent() const { return m_underlyingEvent.get(); }
-    void setUnderlyingEvent(PassRefPtr<Event>);
+    void setUnderlyingEvent(PassRefPtrWillBeRawPtr<Event>);
 
     EventPath& eventPath() { ASSERT(m_eventPath); return *m_eventPath; }
     EventPath& ensureEventPath();
 
     PassRefPtr<NodeList> path() const;
 
     bool isBeingDispatched() const { return eventPhase(); }
 
     virtual void trace(Visitor*);
 
@@ skipping 13 matching lines @@
     bool m_propagationStopped;
     bool m_immediatePropagationStopped;
     bool m_defaultPrevented;
     bool m_defaultHandled;
     bool m_cancelBubble;
 
     unsigned short m_eventPhase;
     EventTarget* m_currentTarget;
     RefPtr<EventTarget> m_target;
     DOMTimeStamp m_createTime;
-    RefPtr<Event> m_underlyingEvent;
+    RefPtrWillBeMember<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