Revert of Pass task runners to AudioManager constructor.

media/mojo/services/mojo_media_client.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 "media/mojo/services/mojo_media_client.h"
 
 namespace media {
 
 MojoMediaClient::MojoMediaClient() {}
 
 MojoMediaClient::~MojoMediaClient() {}
 
 void MojoMediaClient::Initialize() {}
 
-void MojoMediaClient::WillQuit() {}
-
 std::unique_ptr<AudioDecoder> MojoMediaClient::CreateAudioDecoder(
     scoped_refptr<base::SingleThreadTaskRunner> task_runner) {
   return nullptr;
 }
 
 std::unique_ptr<RendererFactory> MojoMediaClient::CreateRendererFactory(
     const scoped_refptr<MediaLog>& media_log) {
   return nullptr;
 }
 
 AudioRendererSink* MojoMediaClient::CreateAudioRendererSink() {
   return nullptr;
 }
 
 VideoRendererSink* MojoMediaClient::CreateVideoRendererSink(
     const scoped_refptr<base::SingleThreadTaskRunner>& task_runner) {
   return nullptr;
 }
 
 std::unique_ptr<CdmFactory> MojoMediaClient::CreateCdmFactory(
     shell::mojom::InterfaceProvider* interface_provider) {
   return nullptr;
 }
 
 }  // namespace media