Get rid of MessageLoop* caching in extensions code.

chrome/browser/utility_process_host.h

 // 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.
 
 #ifndef CHROME_BROWSER_UTILITY_PROCESS_HOST_H_
 #define CHROME_BROWSER_UTILITY_PROCESS_HOST_H_
 
 #include <string>
 
 #include "base/basictypes.h"
 #include "base/ref_counted.h"
 #include "base/task.h"
+#include "chrome/browser/chrome_thread.h"
 #include "chrome/common/child_process_host.h"
 #include "chrome/common/extensions/update_manifest.h"
 #include "ipc/ipc_channel.h"
 
 class CommandLine;
 class DictionaryValue;
 class ListValue;
-class MessageLoop;
 
 // This class acts as the browser-side host to a utility child process.  A
 // utility process is a short-lived sandboxed process that is created to run
 // a specific task.  This class lives solely on the IO thread.
 class UtilityProcessHost : public ChildProcessHost {
  public:
   // An interface to be implemented by consumers of the utility process to
   // get results back.  All functions are called on the thread passed along
   // to UtilityProcessHost.
   class Client : public base::RefCountedThreadSafe<Client> {
@@ skipping 34 matching lines @@
         const std::string& error_message) {}
 
    private:
     friend class UtilityProcessHost;
     void OnMessageReceived(const IPC::Message& message);
 
     DISALLOW_COPY_AND_ASSIGN(Client);
   };
 
   UtilityProcessHost(ResourceDispatcherHost* rdh, Client* client,
-                     MessageLoop* client_loop);
+                     ChromeThread::ID client_thread_id);
   virtual ~UtilityProcessHost();
 
   // Start a process to unpack the extension at the given path.  The process
   // will be given access to the directory subtree that the extension file is
   // in, so the caller is expected to have moved that file into a quarantined
   // location first.
   bool StartExtensionUnpacker(const FilePath& extension);
 
   // Start a process to unpack and parse a web resource from the given JSON
   // data.  Any links that need to be downloaded from the parsed data
@@ skipping 24 matching lines @@
   virtual void OnChannelError();
   virtual bool CanShutdown() { return true; }
   virtual URLRequestContext* GetRequestContext(
       uint32 request_id,
       const ViewHostMsg_Resource_Request& request_data) {
     return NULL;
   }
 
   // A pointer to our client interface, who will be informed of progress.
   scoped_refptr<Client> client_;
-  MessageLoop* client_loop_;
+  ChromeThread::ID client_thread_id_;
 
   DISALLOW_COPY_AND_ASSIGN(UtilityProcessHost);
 };
 
 #endif  // CHROME_BROWSER_UTILITY_PROCESS_HOST_H_