Revert of Pass task runners to AudioManager constructor.

media/audio/win/audio_manager_win.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 "media/audio/audio_io.h"
 
 #include <windows.h>
 #include <objbase.h>  // This has to be before initguid.h
 #include <initguid.h>
 #include <mmsystem.h>
@@ skipping 108 matching lines @@
 
   // Use 4 buffers for Vista, 3 for everyone else:
   //  - The entire Windows audio stack was rewritten for Windows Vista and wave
   //    out performance was degraded compared to XP.
   //  - The regression was fixed in Windows 7 and most configurations will work
   //    with 2, but some (e.g., some Sound Blasters) still need 3.
   //  - Some XP configurations (even multi-processor ones) also need 3.
   return (base::win::GetVersion() == base::win::VERSION_VISTA) ? 4 : 3;
 }
 
-AudioManagerWin::AudioManagerWin(
-    scoped_refptr<base::SingleThreadTaskRunner> task_runner,
-    scoped_refptr<base::SingleThreadTaskRunner> worker_task_runner,
-    AudioLogFactory* audio_log_factory)
-    : AudioManagerBase(std::move(task_runner),
-                       std::move(worker_task_runner),
-                       audio_log_factory),
+AudioManagerWin::AudioManagerWin(AudioLogFactory* audio_log_factory)
+    : AudioManagerBase(audio_log_factory),
       // |CoreAudioUtil::IsSupported()| uses static variables to avoid doing
       // multiple initializations.  This is however not thread safe.
       // So, here we call it explicitly before we kick off the audio thread
       // or do any other work.
-      enumeration_type_(CoreAudioUtil::IsSupported() ? kMMDeviceEnumeration
-                                                     : kWaveEnumeration) {
+      enumeration_type_(CoreAudioUtil::IsSupported() ?
+          kMMDeviceEnumeration : kWaveEnumeration) {
   SetMaxOutputStreamsAllowed(kMaxOutputStreams);
 
   // WARNING: This is executed on the UI loop, do not add any code here which
   // loads libraries or attempts to call out into the OS.  Instead add such code
   // to the InitializeOnAudioThread() method below.
 
   // Task must be posted last to avoid races from handing out "this" to the
   // audio thread.
   GetTaskRunner()->PostTask(FROM_HERE, base::Bind(
       &AudioManagerWin::InitializeOnAudioThread, base::Unretained(this)));
 }
 
 AudioManagerWin::~AudioManagerWin() {
+  // It's safe to post a task here since Shutdown() will wait for all tasks to
+  // complete before returning.
+  GetTaskRunner()->PostTask(FROM_HERE, base::Bind(
+      &AudioManagerWin::ShutdownOnAudioThread, base::Unretained(this)));
   Shutdown();
 }
 
 bool AudioManagerWin::HasAudioOutputDevices() {
   return (::waveOutGetNumDevs() != 0);
 }
 
 bool AudioManagerWin::HasAudioInputDevices() {
   return (::waveInGetNumDevs() != 0);
 }
 
 void AudioManagerWin::InitializeOnAudioThread() {
   DCHECK(GetTaskRunner()->BelongsToCurrentThread());
 
   if (core_audio_supported()) {
     // AudioDeviceListenerWin must be initialized on a COM thread and should
     // only be used if WASAPI / Core Audio is supported.
     output_device_listener_.reset(new AudioDeviceListenerWin(BindToCurrentLoop(
         base::Bind(&AudioManagerWin::NotifyAllOutputDeviceChangeListeners,
                    base::Unretained(this)))));
   }
 }
 
+void AudioManagerWin::ShutdownOnAudioThread() {
+  DCHECK(GetTaskRunner()->BelongsToCurrentThread());
+  output_device_listener_.reset();
+}
+
 base::string16 AudioManagerWin::GetAudioInputDeviceModel() {
   // Get the default audio capture device and its device interface name.
   DWORD device_id = 0;
   waveInMessage(reinterpret_cast<HWAVEIN>(WAVE_MAPPER),
                 DRVM_MAPPER_PREFERRED_GET,
                 reinterpret_cast<DWORD_PTR>(&device_id), NULL);
   ULONG device_interface_name_size = 0;
   waveInMessage(reinterpret_cast<HWAVEIN>(device_id),
                 DRV_QUERYDEVICEINTERFACESIZE,
                 reinterpret_cast<DWORD_PTR>(&device_interface_name_size), 0);
@@ skipping 338 matching lines @@
                   << device_id;
       return NULL;
     }
   }
 
   return new PCMWaveInAudioInputStream(this, params, kNumInputBuffers,
                                        xp_device_id);
 }
 
 /// static
-ScopedAudioManagerPtr CreateAudioManager(
-    scoped_refptr<base::SingleThreadTaskRunner> task_runner,
-    scoped_refptr<base::SingleThreadTaskRunner> worker_task_runner,
-    AudioLogFactory* audio_log_factory) {
-  return ScopedAudioManagerPtr(
-      new AudioManagerWin(std::move(task_runner), std::move(worker_task_runner),
-                          audio_log_factory));
+AudioManager* CreateAudioManager(AudioLogFactory* audio_log_factory) {
+  return new AudioManagerWin(audio_log_factory);
 }
 
 }  // namespace media