Add MessageLoop::QuitNow and use it to terminate a sync IPC....

chrome/renderer/renderer_webkitclient_impl.cc

 // Copyright (c) 2010 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/renderer/renderer_webkitclient_impl.h"
 
 #if defined(USE_SYSTEM_SQLITE)
 #include <sqlite3.h>
 #else
 #include "third_party/sqlite/preprocessed/sqlite3.h"
@@ skipping 113 matching lines @@
       new ViewHostMsg_SetCookie(routing_id, url, first_party_for_cookies,
                                 value_utf8));
 }
 
 WebString RendererWebKitClientImpl::cookies(
     const WebURL& url, const WebURL& first_party_for_cookies) {
   // TODO(darin): Modify WebKit to pass the WebFrame.  This code may be reached
   // when there is no active script context.
   int32 routing_id = RenderThread::RoutingIDForCurrentContext();
 
-  // TODO(darin): We should use SendAndRunNestedMessageLoop here to avoid dead-
-  // locking the browser, but this causes a performance regression.  Switching
-  // back to Send to verify.  See http://crbug.com/36310.
-
   std::string value_utf8;
-  RenderThread::current()->Send(
+  RenderThread::current()->SendAndRunNestedMessageLoop(
       new ViewHostMsg_GetCookies(routing_id, url, first_party_for_cookies,
                                  &value_utf8));
 
   return WebString::fromUTF8(value_utf8);
 }
 
 bool RendererWebKitClientImpl::rawCookies(
     const WebURL& url,
     const WebURL& first_party_for_cookies,
     WebVector<WebKit::WebCookie>* raw_cookies) {
@@ skipping 257 matching lines @@
     const WebKit::WebString& challenge,
     const WebKit::WebURL& url) {
   std::string signed_public_key;
   RenderThread::current()->Send(new ViewHostMsg_Keygen(
       static_cast<uint32>(key_size_index),
       challenge.utf8(),
       GURL(url),
       &signed_public_key));
   return WebString::fromUTF8(signed_public_key);
 }