Remove all remaining traces of MessageLoopProxy.

extensions/shell/browser/shell_browser_main_parts.cc

 // Copyright 2014 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 "extensions/shell/browser/shell_browser_main_parts.h"
 
 #include <string>
 
 #include "base/command_line.h"
 #include "base/run_loop.h"
@@ skipping 188 matching lines @@
       cmd->GetSwitchValueASCII(switches::kAppShellUser),
       cmd->GetSwitchValueASCII(switches::kAppShellRefreshToken)));
 
 #if !defined(DISABLE_NACL)
   // Takes ownership.
   nacl::NaClBrowser::SetDelegate(
       new ShellNaClBrowserDelegate(browser_context_.get()));
   // Track the task so it can be canceled if app_shell shuts down very quickly,
   // such as in browser tests.
   task_tracker_.PostTask(
-      BrowserThread::GetMessageLoopProxyForThread(BrowserThread::IO).get(),
-      FROM_HERE,
+      BrowserThread::GetTaskRunnerForThread(BrowserThread::IO).get(), FROM_HERE,
       base::Bind(nacl::NaClProcessHost::EarlyStartup));
 #endif
 
   devtools_http_handler_.reset(
       content::ShellDevToolsManagerDelegate::CreateHttpHandler(
           browser_context_.get()));
   if (parameters_.ui_task) {
     // For running browser tests.
     parameters_.ui_task->Run();
     delete parameters_.ui_task;
@@ skipping 69 matching lines @@
 }
 
 void ShellBrowserMainParts::CreateExtensionSystem() {
   DCHECK(browser_context_);
   extension_system_ = static_cast<ShellExtensionSystem*>(
       ExtensionSystem::Get(browser_context_.get()));
   extension_system_->InitForRegularProfile(true);
 }
 
 }  // namespace extensions