if (aIID.Equals(kIStreamListenerIID))
if (aIID.Equals(kIPluginStreamInfoIID))
nsresult nsPluginStreamListenerPeer::QueryInterface(const nsIID& aIID,                                                    void** aInstancePtrResult){  NS_PRECONDITION(nsnull != aInstancePtrResult, "null pointer");  if (nsnull == aInstancePtrResult)    return NS_ERROR_NULL_POINTER;  if (aIID.Equals(kIStreamListenerIID))  {    *aInstancePtrResult = (void *)((nsIStreamListener *)this);    AddRef();    return NS_OK;  }  if (aIID.Equals(kIRequestObserverIID))  {    *aInstancePtrResult = (void *)((nsIRequestObserver *)this);    AddRef();    return NS_OK;  }  if (aIID.Equals(kIHttpHeaderVisitorIID))  {    *aInstancePtrResult = (void *)((nsIHttpHeaderVisitor *)this);    AddRef();    return NS_OK;  }  if (aIID.Equals(kISupportsIID))  {    *aInstancePtrResult = (void *)((nsISupports *)((nsIStreamListener *)this));    AddRef();    return NS_OK;  }  return NS_NOINTERFACE;}