nsCOMPtr<nsIPresContext> pc(do_QueryInterface(aContext));  NS_ASSERTION(pc, "not a pres context!");  return mFrame->OnStartContainer(aRequest, pc, aImage);
return mFrame->OnStartContainer(aRequest, aImage);
NS_IMETHODIMP nsBulletListener::OnStartContainer(imgIRequest *aRequest, nsISupports *aContext, imgIContainer *aImage){  if (!mFrame)    return NS_ERROR_FAILURE;  nsCOMPtr<nsIPresContext> pc(do_QueryInterface(aContext));  NS_ASSERTION(pc, "not a pres context!");  return mFrame->OnStartContainer(aRequest, pc, aImage);}