Add support for the audio-output-device switching IPC mechanism to the renderer lower layers (media…

media/audio/null_audio_sink.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/null_audio_sink.h"
 
 #include "base/bind.h"
+#include "base/location.h"
 #include "base/single_thread_task_runner.h"
 #include "media/audio/fake_audio_worker.h"
 #include "media/base/audio_hash.h"
 
 namespace media {
 
 NullAudioSink::NullAudioSink(
     const scoped_refptr<base::SingleThreadTaskRunner>& task_runner)
     : initialized_(false),
       playing_(false),
@@ skipping 45 matching lines @@
 
   fake_worker_->Stop();
   playing_ = false;
 }
 
 bool NullAudioSink::SetVolume(double volume) {
   // Audio is always muted.
   return volume == 0.0;
 }
 
+void NullAudioSink::SwitchOutputDevice(const std::string& device_id,
+                                       const GURL& security_origin,
+                                       const SwitchOutputDeviceCB& callback) {
+  DCHECK(task_runner_->BelongsToCurrentThread());
+  callback.Run(SWITCH_OUTPUT_DEVICE_RESULT_ERROR_NOT_SUPPORTED);
+}
+
 void NullAudioSink::CallRender() {
   DCHECK(task_runner_->BelongsToCurrentThread());
 
   int frames_received = callback_->Render(audio_bus_.get(), 0);
   if (!audio_hash_ || frames_received <= 0)
     return;
 
   audio_hash_->Update(audio_bus_.get(), frames_received);
 }
 
 void NullAudioSink::StartAudioHashForTesting() {
   DCHECK(!initialized_);
   audio_hash_.reset(new AudioHash());
 }
 
 std::string NullAudioSink::GetAudioHashForTesting() {
   return audio_hash_ ? audio_hash_->ToString() : std::string();
 }
 
 }  // namespace media