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

Source/core/events/TouchEvent.h

 /*
  * Copyright 2008, The Android Open Source Project
  * Copyright (C) 2012 Research In Motion Limited. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  *  * Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  *  * Redistributions in binary form must reproduce the above copyright
@@ skipping 52 matching lines @@
     TouchList* changedTouches() const { return m_changedTouches.get(); }
 
     void setTouches(PassRefPtr<TouchList> touches) { m_touches = touches; }
     void setTargetTouches(PassRefPtr<TouchList> targetTouches) { m_targetTouches = targetTouches; }
     void setChangedTouches(PassRefPtr<TouchList> changedTouches) { m_changedTouches = changedTouches; }
 
     virtual bool isTouchEvent() const OVERRIDE;
 
     virtual const AtomicString& interfaceName() const OVERRIDE;
 
+    virtual void trace(Visitor*) OVERRIDE;
+
 private:
     TouchEvent();
     TouchEvent(TouchList* touches, TouchList* targetTouches,
             TouchList* changedTouches, const AtomicString& type,
             PassRefPtr<AbstractView>, int screenX, int screenY, int pageX,
             int pageY,
             bool ctrlKey, bool altKey, bool shiftKey, bool metaKey);
 
     RefPtr<TouchList> m_touches;
     RefPtr<TouchList> m_targetTouches;
     RefPtr<TouchList> m_changedTouches;
 };
 
 class TouchEventDispatchMediator FINAL : public EventDispatchMediator {
 public:
     static PassRefPtr<TouchEventDispatchMediator> create(PassRefPtr<TouchEvent>);
 
 private:
     explicit TouchEventDispatchMediator(PassRefPtr<TouchEvent>);
     TouchEvent* event() const;
     virtual bool dispatchEvent(EventDispatcher*) const OVERRIDE;
 };
 
 DEFINE_EVENT_TYPE_CASTS(TouchEvent);
 
 } // namespace WebCore
 
 #endif // TouchEvent_h