Remove all remaining traces of MessageLoopProxy.

chrome/browser/extensions/startup_helper.cc

 // Copyright (c) 2012 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/browser/extensions/startup_helper.h"
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
 #include "base/command_line.h"
 #include "base/files/file_path.h"
@@ skipping 113 matching lines @@
 
   void FinishOnUIThread() {
     CHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
     if (run_loop_->running())
       run_loop_->Quit();
   }
 
   void StartOnFileThread() {
     CHECK(BrowserThread::CurrentlyOn(BrowserThread::FILE));
     scoped_refptr<base::SingleThreadTaskRunner> file_task_runner =
-        BrowserThread::GetMessageLoopProxyForThread(BrowserThread::FILE);
+        BrowserThread::GetTaskRunnerForThread(BrowserThread::FILE);
 
     scoped_refptr<SandboxedUnpacker> unpacker(new SandboxedUnpacker(
         Manifest::INTERNAL, 0, /* no special creation flags */
         temp_dir_, file_task_runner.get(), this));
     unpacker->StartWithCrx(crx_file_);
   }
 
   // The file being validated.
   const CRXFileInfo& crx_file_;
 
@@ skipping 43 matching lines @@
     *error = base::UTF16ToUTF8(helper->error());
   return success;
 }
 
 StartupHelper::~StartupHelper() {
   if (pack_job_.get())
     pack_job_->ClearClient();
 }
 
 }  // namespace extensions