Enable pulse as the default IO handling in Chrome

media/base/media_switches.h

 // 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.
 
 // Defines all the "media" command-line switches.
 
 #ifndef MEDIA_BASE_MEDIA_SWITCHES_H_
 #define MEDIA_BASE_MEDIA_SWITCHES_H_
 
 #include "build/build_config.h"
 #include "media/base/media_export.h"
 
 namespace switches {
 
 #if defined(OS_LINUX) || defined(OS_FREEBSD) || defined(OS_SOLARIS)
 extern const char kAlsaOutputDevice[];
 extern const char kAlsaInputDevice[];
 #endif
 
 MEDIA_EXPORT extern const char kAudioBufferSize[];
 
 #if defined(USE_CRAS)
 MEDIA_EXPORT extern const char kUseCras[];
 #endif
 
-#if defined(USE_PULSEAUDIO)
-MEDIA_EXPORT extern const char kUsePulseAudio[];
-#endif
-
 #if defined(OS_WIN)
 MEDIA_EXPORT extern const char kEnableExclusiveAudio[];
 #endif
 
 MEDIA_EXPORT extern const char kDisableAudioFallback[];
 
 MEDIA_EXPORT extern const char kDisableAudioOutputResampler[];
 
 MEDIA_EXPORT extern const char kDisableRendererSideMixing[];
 
 MEDIA_EXPORT extern const char kEnableAudioMixer[];
 
 MEDIA_EXPORT extern const char kEnableWebAudioInput[];
 
 MEDIA_EXPORT extern const char kVideoThreads[];
 
 MEDIA_EXPORT extern const char kDisableEncryptedMedia[];
 
 MEDIA_EXPORT extern const char kEnableOpusPlayback[];
 
 MEDIA_EXPORT extern const char kEnableVp9Playback[];
 
 #if defined(OS_WIN)
 MEDIA_EXPORT extern const char kWaveOutBuffers[];
 #endif
 
 }  // namespace switches
 
 #endif  // MEDIA_BASE_MEDIA_SWITCHES_H_