Remove all remaining traces of MessageLoopProxy.

chrome/renderer/media/cast_session.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/renderer/media/cast_session.h"
 
 #include <stddef.h>
 
 #include <memory>
 #include <utility>
@@ skipping 28 matching lines @@
   if (!shm->Map(size)) {
     NOTREACHED() << "Map failed";
   }
   callback.Run(std::move(shm));
 }
 
 }  // namespace
 
 CastSession::CastSession()
     : delegate_(new CastSessionDelegate()),
-      io_task_runner_(
-          content::RenderThread::Get()->GetIOMessageLoopProxy()) {}
+      io_task_runner_(content::RenderThread::Get()->GetIOTaskRunner()) {}
 
 CastSession::~CastSession() {
   // We should always be able to delete the object on the IO thread.
   CHECK(io_task_runner_->DeleteSoon(FROM_HERE, delegate_.release()));
 }
 
 void CastSession::StartAudio(const media::cast::AudioSenderConfig& config,
                              const AudioFrameInputAvailableCallback& callback,
                              const ErrorCallback& error_callback) {
   DCHECK(content::RenderThread::Get());
@@ skipping 62 matching lines @@
 
 void CastSession::GetStatsAndReset(bool is_audio,
                                    const StatsCallback& callback) {
   io_task_runner_->PostTask(
       FROM_HERE,
       base::Bind(&CastSessionDelegate::GetStatsAndReset,
                  base::Unretained(delegate_.get()),
                  is_audio,
                  media::BindToCurrentLoop(callback)));
 }