Enable setting deferral state on ResourceDispatcher at request start

content/child/web_url_loader_impl.cc

 // Copyright 2014 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/web_url_loader_impl.h"
 
 #include <stdint.h>
 
 #include <algorithm>
 #include <memory>
@@ skipping 537 matching lines @@
   // contains the body of the response. The network request has already been
   // made by the browser.
   if (stream_override_.get()) {
     CHECK(IsBrowserSideNavigationEnabled());
     DCHECK(!sync_load_response);
     DCHECK_NE(WebURLRequest::FrameTypeNone, request.getFrameType());
     request_info.resource_body_stream_url = stream_override_->stream_url;
   }
 
   if (sync_load_response) {
+    DCHECK(defers_loading_ == NOT_DEFERRING);
     resource_dispatcher_->StartSync(
         request_info, request_body.get(), sync_load_response);
     return;
   }
 
   request_id_ = resource_dispatcher_->StartAsync(
       request_info, request_body.get(),
       base::WrapUnique(new WebURLLoaderImpl::RequestPeerImpl(this)));
+
+  if (defers_loading_ != NOT_DEFERRING)
+    resource_dispatcher_->SetDefersLoading(request_id_, true);
 }
 
 void WebURLLoaderImpl::Context::SetWebTaskRunner(
     std::unique_ptr<blink::WebTaskRunner> web_task_runner) {
   web_task_runner_ = std::move(web_task_runner);
 }
 
 void WebURLLoaderImpl::Context::OnUploadProgress(uint64_t position,
                                                  uint64_t size) {
   if (client_)
@@ skipping 603 matching lines @@
     response->clearHTTPHeaderField(webStringName);
     while (response_headers->EnumerateHeader(&iterator, name, &value)) {
       response->addHTTPHeaderField(webStringName,
                                    WebString::fromLatin1(value));
     }
   }
   return true;
 }
 
 }  // namespace content