Fix a crash due to UserScriptListener unregistering notifications on the wrong

chrome/browser/renderer_host/resource_dispatcher_host.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.
 
 // See http://dev.chromium.org/developers/design-documents/multi-process-resource-loading
 
 #include "chrome/browser/renderer_host/resource_dispatcher_host.h"
 
 #include <vector>
 
@@ skipping 176 matching lines @@
       receiver_(NULL) {
   ResourceQueue::DelegateSet resource_queue_delegates;
   resource_queue_delegates.insert(user_script_listener_.get());
   resource_queue_.Initialize(resource_queue_delegates);
 }
 
 ResourceDispatcherHost::~ResourceDispatcherHost() {
   AsyncResourceHandler::GlobalCleanup();
   STLDeleteValues(&pending_requests_);
 
+  user_script_listener_->ShutdownMainThread();
+
   // Clear blocked requests if any left.
   // Note that we have to do this in 2 passes as we cannot call
   // CancelBlockedRequestsForRoute while iterating over
   // blocked_requests_map_, as it modifies it.
   std::set<ProcessRouteIDs> ids;
   for (BlockedRequestMap::const_iterator iter = blocked_requests_map_.begin();
        iter != blocked_requests_map_.end(); ++iter) {
     std::pair<std::set<ProcessRouteIDs>::iterator, bool> result =
         ids.insert(iter->first);
     // We should not have duplicates.
@@ skipping 1550 matching lines @@
     const ResourceType::Type& resource_type,
     ResourceDispatcherHostRequestInfo* request_info) {
   // Apply filter only to chrome extension css files that don't have
   // security filter already set.
   if (url.SchemeIs(chrome::kExtensionScheme) &&
       request_info->filter_policy() == FilterPolicy::DONT_FILTER &&
       resource_type == ResourceType::STYLESHEET) {
     request_info->set_filter_policy(FilterPolicy::FILTER_EXTENSION_MESSAGES);
   }
 }