Oilpan: Move the EventListener hierarchy to Oilpan's heap

Source/core/dom/MessagePort.h

 /*
  * Copyright (C) 2008 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:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 75 matching lines @@
     bool started() const { return m_started; }
 
     const AtomicString& interfaceName() const override;
     ExecutionContext* executionContext() const override { return ActiveDOMObject::executionContext(); }
     MessagePort* toMessagePort() override { return this; }
 
     // ActiveDOMObject implementation.
     bool hasPendingActivity() const override;
     void stop() override { close(); }
 
-    void setOnmessage(PassRefPtr<EventListener> listener)
+    void setOnmessage(PassRefPtrWillBeRawPtr<EventListener> listener)
     {
         setAttributeEventListener(EventTypeNames::message, listener);
         start();
     }
     EventListener* onmessage() { return getAttributeEventListener(EventTypeNames::message); }
 
     // A port starts out its life entangled, and remains entangled until it is closed or is cloned.
     bool isEntangled() const { return !m_closed && !isNeutered(); }
 
     // A port gets neutered when it is transferred to a new owner via postMessage().
@@ skipping 18 matching lines @@
     bool m_closed;
 
     WeakPtrFactory<MessagePort> m_weakFactory;
 
     RefPtr<ScriptState> m_scriptStateForConversion;
 };
 
 } // namespace blink
 
 #endif // MessagePort_h