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();

[Guido Urdaneta, 2017/02/15 15:40:06]

Should this be UnavailableDeviceParams()?

[o1ka, 2017/02/15 15:45:07]

The client usually needs to check for parameter validity anyways. Also,
AudioManager returns invalid parameters in one case on Windows now, so returning
invalid parameters looks natural.
Whatever we decide here, Input needs to be symmetrical; and Tommi wanted to
switch AudioManager to return invalid parameters for input.
WDYT?

[Guido Urdaneta, 2017/02/15 15:47:25]

Makes sense.

+
+  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