Make Event RefCountedGarbageCollected and implement trace() methods to the Event hierarcy

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 26 matching lines @@
 class EventDispatcher;
 class HTMLIFrameElement;
 
 struct EventInit {
     EventInit();
 
     bool bubbles;
     bool cancelable;
 };
 
-class Event : public ScriptWrappable, public RefCounted<Event> {
+class Event : public RefCountedWillBeRefCountedGarbageCollected<Event>,  public ScriptWrappable {
 public:
     enum PhaseType {
         NONE                = 0,
         CAPTURING_PHASE     = 1,
         AT_TARGET           = 2,
         BUBBLING_PHASE      = 3
     };
 
     enum EventType {
         MOUSEDOWN           = 1,
@@ skipping 114 matching lines @@
     Event* underlyingEvent() const { return m_underlyingEvent.get(); }
     void setUnderlyingEvent(PassRefPtr<Event>);
 
     EventPath& eventPath() { ASSERT(m_eventPath); return *m_eventPath; }
     EventPath& ensureEventPath();
 
     PassRefPtr<NodeList> path() const;
 
     bool isBeingDispatched() const { return eventPhase(); }
 
+    virtual void trace(Visitor*);
+
 protected:
     Event();
     Event(const AtomicString& type, bool canBubble, bool cancelable);
     Event(const AtomicString& type, const EventInit&);
 
     virtual void receivedTarget();
     bool dispatched() const { return m_target; }
 
 private:
     AtomicString m_type;
     bool m_canBubble;
     bool m_cancelable;
 
     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;

[Erik Corry, 2014/02/28 14:08:52]

I wonder why this was not a traced Member?

     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