Moving file_system_proxy to base/ and changing it to work with MessageLoopPro...

chrome/browser/chrome_thread_relay.h

-// 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.
-
-// ChromeThreadRelay provides a convenient way to bounce work to a specific
-// ChromeThread and then return results back to the originating thread.
-//
-// EXAMPLE:
-//
-//  class MyRelay : public ChromeThreadRelay {
-//   public:
-//    MyRelay(const Params& params) : params_(params) {
-//    }
-//   protected:
-//    virtual void RunWork() {
-//      results_ = DoWork(params_);
-//    }
-//    virtual void RunCallback() {
-//      ... use results_ on the originating thread ...
-//    }
-//   private:
-//    Params params_;
-//    Results_ results_;
-//  };
-
-#ifndef CHROME_BROWSER_CHROME_THREAD_RELAY_H_
-#define CHROME_BROWSER_CHROME_THREAD_RELAY_H_
-
-#include "base/ref_counted.h"
-#include "chrome/browser/chrome_thread.h"
-
-class ChromeThreadRelay
-    : public base::RefCountedThreadSafe<ChromeThreadRelay> {
- public:
-  ChromeThreadRelay();
-
-  void Start(ChromeThread::ID target_thread_id,
-             const tracked_objects::Location& from_here);
-
- protected:
-  friend class base::RefCountedThreadSafe<ChromeThreadRelay>;
-  virtual ~ChromeThreadRelay() {}
-
-  // Called to perform work on the FILE thread.
-  virtual void RunWork() = 0;
-
-  // Called to notify the callback on the origin thread.
-  virtual void RunCallback() = 0;
-
- private:
-  void ProcessOnTargetThread();
-  ChromeThread::ID origin_thread_id_;
-};
-
-#endif  // CHROME_BROWSER_CHROME_THREAD_RELAY_H_