mStreamObserver = null_nsCOMPtr();
nsDocLoaderImpl::Stop(void){  nsresult rv = NS_OK;  PR_LOG(gDocLoaderLog, PR_LOG_DEBUG,          ("DocLoader:%p: Stop() called\n", this));  rv = mLoadGroup->Cancel();  /*    * Release the Stream Observer...     * It will be set on the next LoadDocument(...)    */  mStreamObserver = null_nsCOMPtr();  return rv;}       