Avoid leaking objects between isolated worlds via attribute event listeners

Source/modules/notifications/Notification.h

 /*
  * Copyright (C) 2009 Google Inc. All rights reserved.
  * Copyright (C) 2009, 2011, 2012 Apple Inc. 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.
@@ skipping 97 matching lines @@
     String replaceId() const { return tag(); }
     void setReplaceId(const String& replaceId) { setTag(replaceId); }
 #endif
 
     String tag() const { return m_tag; }
     void setTag(const String& tag) { m_tag = tag; }
 
     TextDirection direction() const { return dir() == "rtl" ? RTL : LTR; }
 
 #if ENABLE(LEGACY_NOTIFICATIONS)
-    EventListener* ondisplay() { return getAttributeEventListener(eventNames().showEvent); }
-    void setOndisplay(PassRefPtr<EventListener> listener) { setAttributeEventListener(eventNames().showEvent, listener); }
+    DEFINE_MAPPED_ATTRIBUTE_EVENT_LISTENER(display, show);
 #endif
     DEFINE_ATTRIBUTE_EVENT_LISTENER(show);
     DEFINE_ATTRIBUTE_EVENT_LISTENER(error);
     DEFINE_ATTRIBUTE_EVENT_LISTENER(close);
     DEFINE_ATTRIBUTE_EVENT_LISTENER(click);
 
     void dispatchClickEvent();
     void dispatchCloseEvent();
     void dispatchErrorEvent();
     void dispatchShowEvent();
@@ skipping 74 matching lines @@
 #if ENABLE(NOTIFICATIONS)
     OwnPtr<Timer<Notification> > m_taskTimer;
 #endif
 };
 
 } // namespace WebCore
 
 #endif // ENABLE(NOTIFICATIONS) || ENABLE(LEGACY_NOTIFICATIONS)
 
 #endif // Notifications_h