Create a content::ResourceContext.

content/browser/renderer_host/resource_dispatcher_host.cc

 // Copyright (c) 2011 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.
 
 // See http://dev.chromium.org/developers/design-documents/multi-process-resource-loading
 
 #include "content/browser/renderer_host/resource_dispatcher_host.h"
 
 #include <set>
 #include <vector>
@@ skipping 1571 matching lines @@
 static int GetCertID(net::URLRequest* request, int child_id) {
   if (request->ssl_info().cert) {
     return CertStore::GetInstance()->StoreCert(request->ssl_info().cert,
                                                child_id);
   }
   return 0;
 }
 
 void ResourceDispatcherHost::NotifyResponseStarted(net::URLRequest* request,
                                                    int child_id) {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
   // Notify the observers on the IO thread.
   FOR_EACH_OBSERVER(Observer, observer_list_, OnRequestStarted(this, request));
 
   int render_process_id, render_view_id;
   if (!RenderViewForRequest(request, &render_process_id, &render_view_id))
     return;
 
   // Notify the observers on the UI thread.
   ResourceRequestDetails* detail = new ResourceRequestDetails(
       request, GetCertID(request, child_id));
@@ skipping 351 matching lines @@
   return is_prefetch_enabled_;
 }
 
 // static
 void ResourceDispatcherHost::set_is_prefetch_enabled(bool value) {
   is_prefetch_enabled_ = value;
 }
 
 // static
 bool ResourceDispatcherHost::is_prefetch_enabled_ = false;