channel to InternalResponse body

gistfile1.cpp

nsCOMPtr<nsIInputStream> reader;
nsCOMPtr<nsIOutputStream> writer;

nsresult rv = NS_NewPipe(getter_AddRefs(reader), getter_AddRefs(writer),
                         0, UINT32_MAX, // unlimited size to avoid writer WOULD_BLOCK case
                         true, true); // non-blocking reader/writer
NS_ENSURE_SUCCESS(rv, rv);

nsRefPtr<InternalResponse> ir = new InternalResponse();
ir->SetBody(reader);
nsRefPtr<Response> response = new Response(global, ir);

nsCOMPtr<nsIStreamListenerTee> tee = do_CreateInstance(NS_STREAMLISTENERTEE_CONTRACTID);
rv = tee->Init(loader, writer, nullptr);
NS_ENSURE_SUCCESS(rv, rv);

channel->AsyncOpen(tee, ...);