nsIContent* content = mOwner->GetContent();
nsIContent* content = aFrame->GetContent();
nsPluginInstanceOwner::Destroy(){  nsIContent* content = mOwner->GetContent();  // stop the timer explicitly to reduce reference count.  CancelTimer();  // unregister context menu listener  if (mCXMenuListener) {    mCXMenuListener->Destroy(mOwner);        NS_RELEASE(mCXMenuListener);  }  nsCOMPtr<nsIDOMEventReceiver> receiver(do_QueryInterface(content));  if (receiver) {    nsCOMPtr<nsIDOMEventListener> listener;    QueryInterface(NS_GET_IID(nsIDOMEventListener), getter_AddRefs(listener));    // Unregister focus event listener    receiver->RemoveEventListenerByIID(listener, NS_GET_IID(nsIDOMFocusListener));    // Unregister mouse event listener    receiver->RemoveEventListenerByIID(listener, NS_GET_IID(nsIDOMMouseListener));    // now for the mouse motion listener    receiver->RemoveEventListenerByIID(listener, NS_GET_IID(nsIDOMMouseMotionListener));    // Unregister key event listener;    receiver->RemoveEventListener(NS_LITERAL_STRING("keypress"), listener, PR_TRUE);    receiver->RemoveEventListener(NS_LITERAL_STRING("keydown"), listener, PR_TRUE);    receiver->RemoveEventListener(NS_LITERAL_STRING("keyup"), listener, PR_TRUE);    // Unregister drag event listener;    receiver->RemoveEventListener(NS_LITERAL_STRING("dragdrop"), listener, PR_TRUE);    receiver->RemoveEventListener(NS_LITERAL_STRING("dragover"), listener, PR_TRUE);    receiver->RemoveEventListener(NS_LITERAL_STRING("dragexit"), listener, PR_TRUE);    receiver->RemoveEventListener(NS_LITERAL_STRING("dragenter"), listener, PR_TRUE);    receiver->RemoveEventListener(NS_LITERAL_STRING("draggesture"), listener, PR_TRUE);  }  // Unregister scroll position listener  nsIFrame* parentWithView = mOwner->GetAncestorWithView();  nsIView* curView = parentWithView ? parentWithView->GetView() : nsnull;  while (curView)  {    nsIScrollableView* scrollingView;    if (NS_SUCCEEDED(CallQueryInterface(curView, &scrollingView)))      scrollingView->RemoveScrollPositionListener((nsIScrollPositionListener *)this);        curView = curView->GetParent();  }  mOwner = nsnull; // break relationship between frame and plugin instance owner  return NS_OK;}