[Net] Propagate priority changes from URLRequest to HttpTransaction

chrome/browser/renderer_host/chrome_resource_dispatcher_host_delegate.cc

 // Copyright (c) 2012 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 "chrome/browser/renderer_host/chrome_resource_dispatcher_host_delegate.h"
 
 #include <string>
 
 #include "base/base64.h"
 #include "base/logging.h"
@@ skipping 130 matching lines @@
     ScopedVector<content::ResourceThrottle>* throttles) {
   if (is_continuation_of_transferred_request)
     ChromeURLRequestUserData::Delete(request);
 
   ChromeURLRequestUserData* user_data =
       ChromeURLRequestUserData::Create(request);
   bool is_prerendering = prerender_tracker_->IsPrerenderingOnIOThread(
       child_id, route_id);
   if (is_prerendering) {
     user_data->set_is_prerender(true);
-    request->set_priority(net::IDLE);
+    request->SetPriority(net::IDLE);
   }
 
 #if defined(OS_ANDROID)
   if (!is_prerendering && resource_type == ResourceType::MAIN_FRAME) {
     throttles->push_back(
         components::InterceptNavigationDelegate::CreateThrottleFor(request));
   }
 #endif
 #if defined(OS_CHROMEOS)
   if (resource_type == ResourceType::MAIN_FRAME) {
@@ skipping 290 matching lines @@
                                               info->GetChildID(),
                                               info->GetRouteID());
   AppendChromeSyncGaiaHeader(request, resource_context);
 #endif
 
   if (io_data->resource_prefetch_predictor_observer()) {
     io_data->resource_prefetch_predictor_observer()->OnRequestRedirected(
         redirect_url, request);
   }
 }