[Mojo-Loading] OnStartLoadingResponseBody should be called after OnReceiveResponse

content/child/url_loader_client_impl.cc

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "content/child/url_loader_client_impl.h"
 
 #include "base/callback.h"
 #include "base/single_thread_task_runner.h"
 #include "content/child/resource_dispatcher.h"
 #include "content/child/url_response_body_consumer.h"
@@ skipping 96 matching lines @@
     DCHECK_EQ(messages.back().type(),
               static_cast<uint32_t>(ResourceMsg_RequestComplete::ID));
     Dispatch(messages.back());
   }
 }
 
 void URLLoaderClientImpl::OnReceiveResponse(
     const ResourceResponseHead& response_head,
     mojom::DownloadedTempFilePtr downloaded_file) {
   has_received_response_ = true;
-  if (body_consumer_)
-    body_consumer_->Start();
   downloaded_file_ = std::move(downloaded_file);
   Dispatch(ResourceMsg_ReceivedResponse(request_id_, response_head));
 }
 
 void URLLoaderClientImpl::OnReceiveRedirect(
     const net::RedirectInfo& redirect_info,
     const ResourceResponseHead& response_head) {
   DCHECK(!has_received_response_);
   DCHECK(!body_consumer_);
   Dispatch(
@@ skipping 17 matching lines @@
     accumulated_transfer_size_diff_during_deferred_ += transfer_size_diff;
   } else {
     resource_dispatcher_->OnTransferSizeUpdated(request_id_,
                                                 transfer_size_diff);
   }
 }
 
 void URLLoaderClientImpl::OnStartLoadingResponseBody(
     mojo::ScopedDataPipeConsumerHandle body) {
   DCHECK(!body_consumer_);
+  DCHECK(has_received_response_);
   body_consumer_ = new URLResponseBodyConsumer(
       request_id_, resource_dispatcher_, std::move(body), task_runner_);
-  if (has_received_response_)
-    body_consumer_->Start();
   if (is_deferred_)
     body_consumer_->SetDefersLoading();
 }
 
 void URLLoaderClientImpl::OnComplete(
     const ResourceRequestCompletionStatus& status) {
   if (!body_consumer_) {
     Dispatch(ResourceMsg_RequestComplete(request_id_, status));
     return;
   }
   body_consumer_->OnComplete(status);
 }
 
 void URLLoaderClientImpl::Dispatch(const IPC::Message& message) {
   if (is_deferred_) {
     deferred_messages_.push_back(message);
   } else if (deferred_messages_.size() > 0) {
     deferred_messages_.push_back(message);
     FlushDeferredMessages();
   } else {
     resource_dispatcher_->DispatchMessage(message);
   }
 }
 
 }  // namespace content