Make IDL Callbacks non-refcounted by default

Source/modules/webmidi/MIDIAccessPromise.h

 /*
  * Copyright (C) 2013 Google 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.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 44 matching lines @@
 
     // ActiveDOMObject
     virtual bool hasPendingActivity() const OVERRIDE;
     virtual void stop() OVERRIDE;
 
     MIDIOptions* options() { return m_options.get(); }
 
     void fulfill();
     void reject(PassRefPtr<DOMError>);
 
-    void then(PassRefPtr<MIDISuccessCallback>, PassRefPtr<MIDIErrorCallback>);
+    void then(PassOwnPtr<MIDISuccessCallback>, PassOwnPtr<MIDIErrorCallback>);
 
 private:
     enum State {
         Pending,
         Accepted,
         Rejected,
         Invoked,
     };
 
     MIDIAccessPromise(ExecutionContext*, const Dictionary&);
 
     void clear();
 
     State m_state;
-    RefPtr<MIDISuccessCallback> m_successCallback;
-    RefPtr<MIDIErrorCallback> m_errorCallback;
+    OwnPtr<MIDISuccessCallback> m_successCallback;
+    OwnPtr<MIDIErrorCallback> m_errorCallback;
     OwnPtr<MIDIOptions> m_options;
     RefPtr<DOMError> m_error;
     RefPtr<MIDIAccess> m_access;
 };
 
 } // namespace WebCore
 
 #endif // MIDIAccessPromise_h