Fix race in PluginDataRemoverImpl going away while it's still being used on the IO thread...

content/browser/plugin_service.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.
 
 #include "content/browser/plugin_service.h"
 
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "base/compiler_specific.h"
 #include "base/file_path.h"
@@ skipping 314 matching lines @@
   return PpapiPluginProcessHost::CreateBrokerHost(*info);
 }
 
 void PluginService::OpenChannelToNpapiPlugin(
     int render_process_id,
     int render_view_id,
     const GURL& url,
     const GURL& page_url,
     const std::string& mime_type,
     PluginProcessHost::Client* client) {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
   DCHECK(!ContainsKey(pending_plugin_clients_, client));
   pending_plugin_clients_.insert(client);
 
   // Make sure plugins are loaded if necessary.
   content::PluginServiceFilterParams params = {
     render_process_id,
     render_view_id,
     page_url,
     &client->GetResourceContext()
   };
@@ skipping 304 matching lines @@
   plugin_list_ = plugin_list;
 }
 
 void PluginService::RegisterInternalPlugin(const webkit::WebPluginInfo& info) {
   plugin_list()->RegisterInternalPlugin(info);
 }
 
 string16 PluginService::GetPluginGroupName(const std::string& plugin_name) {
   return plugin_list()->GetPluginGroupName(plugin_name);
 }