Reland of Switching AudioOutputAuthorizationHandler from using AudioManager interface to AudioSystem one.

media/audio/audio_system_impl.cc

 // Copyright 2017 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_system_impl.h"
 
 #include "base/memory/ptr_util.h"
 #include "base/single_thread_task_runner.h"
 #include "base/task_runner_util.h"
+#include "media/audio/audio_device_description.h"
 #include "media/audio/audio_manager.h"
 
 // Using base::Unretained for |audio_manager_| is safe since it is deleted after
 // its task runner, and AudioSystemImpl is deleted on the UI thread after the IO
 // thread has been stopped and before |audio_manager_| deletion is scheduled.
 namespace media {
 
 namespace {
 
 AudioParameters GetInputParametersOnDeviceThread(AudioManager* audio_manager,
                                                  const std::string& device_id) {
   DCHECK(audio_manager->GetTaskRunner()->BelongsToCurrentThread());
 
   // TODO(olka): remove this when AudioManager::GetInputStreamParameters()
-  // works this way on all the platforms.
+  // returns invalid parameters if the device is not found.
   if (!audio_manager->HasAudioInputDevices())
     return AudioParameters();
 
   return audio_manager->GetInputStreamParameters(device_id);
 }
 
+AudioParameters GetOutputParametersOnDeviceThread(
+    AudioManager* audio_manager,
+    const std::string& device_id) {
+  DCHECK(audio_manager->GetTaskRunner()->BelongsToCurrentThread());
+
+  // TODO(olka): remove this when
+  // AudioManager::Get[Default]OutputStreamParameters() returns invalid
+  // parameters if the device is not found.
+  if (!audio_manager->HasAudioOutputDevices())
+    return AudioParameters();
+
+  return media::AudioDeviceDescription::IsDefaultDevice(device_id)
+             ? audio_manager->GetDefaultOutputStreamParameters()
+             : audio_manager->GetOutputStreamParameters(device_id);
+}
+
 }  // namespace
 
 AudioSystemImpl::AudioSystemImpl(AudioManager* audio_manager)
     : audio_manager_(audio_manager) {
   DCHECK(audio_manager_);
   AudioSystem::SetInstance(this);
 }
 
 AudioSystemImpl::~AudioSystemImpl() {
   AudioSystem::ClearInstance(this);
@@ skipping 14 matching lines @@
                                                 audio_manager_, device_id)));
     return;
   }
   base::PostTaskAndReplyWithResult(
       GetTaskRunner(), FROM_HERE,
       base::Bind(&GetInputParametersOnDeviceThread,
                  base::Unretained(audio_manager_), device_id),
       std::move(on_params_cb));
 }
 
+void AudioSystemImpl::GetOutputStreamParameters(
+    const std::string& device_id,
+    OnAudioParamsCallback on_params_cb) const {
+  if (GetTaskRunner()->BelongsToCurrentThread()) {
+    GetTaskRunner()->PostTask(
+        FROM_HERE, base::Bind(on_params_cb, GetOutputParametersOnDeviceThread(
+                                                audio_manager_, device_id)));
+    return;
+  }
+  base::PostTaskAndReplyWithResult(
+      GetTaskRunner(), FROM_HERE,
+      base::Bind(&GetOutputParametersOnDeviceThread,
+                 base::Unretained(audio_manager_), device_id),
+      std::move(on_params_cb));
+}
+
 void AudioSystemImpl::HasInputDevices(OnBoolCallback on_has_devices_cb) const {
   if (GetTaskRunner()->BelongsToCurrentThread()) {
     GetTaskRunner()->PostTask(
         FROM_HERE,
         base::Bind(on_has_devices_cb, audio_manager_->HasAudioInputDevices()));
     return;
   }
   base::PostTaskAndReplyWithResult(
       GetTaskRunner(), FROM_HERE,
       base::Bind(&AudioManager::HasAudioInputDevices,
                  base::Unretained(audio_manager_)),
       std::move(on_has_devices_cb));
 }
 
 AudioManager* AudioSystemImpl::GetAudioManager() const {
   return audio_manager_;
 }
 
 base::SingleThreadTaskRunner* AudioSystemImpl::GetTaskRunner() const {
   return audio_manager_->GetTaskRunner();
 }
 
 }  // namespace media