Remove all remaining traces of MessageLoopProxy.

chrome/browser/apps/app_shim/app_shim_host_mac.cc

 // Copyright 2013 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/apps/app_shim/app_shim_host_mac.h"
 
 #include "base/bind.h"
 #include "base/files/file_path.h"
 #include "base/logging.h"
 #include "chrome/browser/apps/app_shim/app_shim_handler_mac.h"
 #include "chrome/common/mac/app_shim_messages.h"
 #include "content/public/browser/browser_thread.h"
 #include "ipc/ipc_channel_proxy.h"
 
 AppShimHost::AppShimHost() : initial_launch_finished_(false) {}
 
 AppShimHost::~AppShimHost() {
   DCHECK(CalledOnValidThread());
   apps::AppShimHandler* handler = apps::AppShimHandler::GetForAppMode(app_id_);
   if (handler)
     handler->OnShimClose(this);
 }
 
 void AppShimHost::ServeChannel(const IPC::ChannelHandle& handle) {
   DCHECK(CalledOnValidThread());
   DCHECK(!channel_.get());
   channel_ = IPC::ChannelProxy::Create(
-      handle,
-      IPC::Channel::MODE_SERVER,
-      this,
-      content::BrowserThread::GetMessageLoopProxyForThread(
-          content::BrowserThread::IO).get());
+      handle, IPC::Channel::MODE_SERVER, this,
+      content::BrowserThread::GetTaskRunnerForThread(content::BrowserThread::IO)
+          .get());
 }
 
 base::FilePath AppShimHost::GetProfilePath() const {
   return profile_path_;
 }
 
 std::string AppShimHost::GetAppId() const {
   return app_id_;
 }
 
@@ skipping 82 matching lines @@
 }
 
 void AppShimHost::OnAppRequestUserAttention(apps::AppShimAttentionType type) {
   Send(new AppShimMsg_SetUserAttention(type));
 }
 
 void AppShimHost::Close() {
   DCHECK(CalledOnValidThread());
   delete this;
 }