Move initialization of ChromeURLRequestContexts to the IO thread.

chrome/browser/renderer_host/resource_dispatcher_host.cc

 // Copyright (c) 2009 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 "chrome/browser/renderer_host/resource_dispatcher_host.h"
 
 #include <vector>
 
@@ skipping 384 matching lines @@
 void ResourceDispatcherHost::BeginRequest(
     int request_id,
     const ViewHostMsg_Resource_Request& request_data,
     IPC::Message* sync_result,  // only valid for sync
     int route_id) {
   ChildProcessInfo::ProcessType process_type = receiver_->type();
   int child_id = receiver_->id();
   ChromeURLRequestContext* context = static_cast<ChromeURLRequestContext*>(
       receiver_->GetRequestContext(request_id, request_data));
   if (!context) {
-    context = static_cast<ChromeURLRequestContext*>(
-        Profile::GetDefaultRequestContext());
+    URLRequestContextGetter* context_getter =
+        Profile::GetDefaultRequestContext();
+    if (context_getter) {
+      context = static_cast<ChromeURLRequestContext*>(
+          context_getter->GetURLRequestContext());
+    }
   }
 
   if (is_shutdown_ ||
       !ShouldServiceRequest(process_type, child_id, request_data)) {
     URLRequestStatus status(URLRequestStatus::FAILED, net::ERR_ABORTED);
     if (sync_result) {
       SyncLoadResult result;
       result.status = status;
       ViewHostMsg_SyncLoad::WriteReplyParams(sync_result, result);
       receiver_->Send(sync_result);
@@ skipping 1382 matching lines @@
     case ViewHostMsg_UploadProgress_ACK::ID:
     case ViewHostMsg_SyncLoad::ID:
       return true;
 
     default:
       break;
   }
 
   return false;
 }