Reduce/remove usage of BrowserThread in content/browser/loader.

content/browser/browser_main_loop.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 "content/browser/browser_main_loop.h"
 
 #include <stddef.h>
 
 #include <string>
 #include <utility>
@@ skipping 1486 matching lines @@
 
   // RDH needs the IO thread to be created
   {
     TRACE_EVENT0("startup",
       "BrowserMainLoop::BrowserThreadsStarted:InitResourceDispatcherHost");
     // TODO(ananta)
     // We register an interceptor on the ResourceDispatcherHostImpl instance to
     // intercept requests to create handlers for download requests. We need to
     // find a better way to achieve this. Ideally we don't want knowledge of
     // downloads in ResourceDispatcherHostImpl.
+    // We pass the task runners for the UI and IO threads as a stopgap approach
+    // for now. Eventually variants of these runners would be available in the
+    // network service.
     resource_dispatcher_host_.reset(new ResourceDispatcherHostImpl(
-        base::Bind(&DownloadResourceHandler::Create)));
+        base::Bind(&DownloadResourceHandler::Create),
+        BrowserThread::GetTaskRunnerForThread(BrowserThread::IO)));
     GetContentClient()->browser()->ResourceDispatcherHostCreated();
 
     loader_delegate_.reset(new LoaderDelegateImpl());
     resource_dispatcher_host_->SetLoaderDelegate(loader_delegate_.get());
   }
 
   // MediaStreamManager needs the IO thread to be created.
   {
     TRACE_EVENT0("startup",
       "BrowserMainLoop::BrowserThreadsStarted:InitMediaStreamManager");
@@ skipping 254 matching lines @@
         BrowserThread::GetTaskRunnerForThread(BrowserThread::FILE),
         MediaInternals::GetInstance());
   }
   CHECK(audio_manager_);
 
   audio_system_ = media::AudioSystemImpl::Create(audio_manager_.get());
   CHECK(audio_system_);
 }
 
 }  // namespace content