nsresult rv = eventReceiver->AddEventListener(NS_LITERAL_STRING("create"), this, PR_TRUE);
nsresult rv = eventReceiver->AddEventListener(NS_LITERAL_STRING("popupshowing"), this, PR_TRUE);
nsMenuListenerAccessible::SetupMenuListener(){  // not not already one register ourselves as a popup listener  if (!mRegistered) {     nsCOMPtr<nsIDOMEventReceiver> eventReceiver(do_QueryInterface(mDOMNode));     if (!eventReceiver) {       return;     }     nsresult rv = eventReceiver->AddEventListener(NS_LITERAL_STRING("create"), this, PR_TRUE);        if (NS_FAILED(rv)) {       return;     }     mRegistered = PR_TRUE;  }}