Add AudioManager::GetAudioOutputDeviceNames and implement for pulseaudio.

media/audio/audio_manager_unittest.cc

+// Copyright 2013 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 "base/logging.h"
+#include "base/memory/scoped_ptr.h"
+#include "media/audio/audio_manager.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+namespace media {
+
+class AudioManagerTest : public ::testing::Test {
+ protected:
+  AudioManagerTest() : audio_manager_(AudioManager::Create()) {}
+
+  scoped_ptr<AudioManager> audio_manager_;
+};
+
+// TODO(joi): Remove guards once implemented for all platforms.
+#if defined(USE_PULSEAUDIO)
+TEST_F(AudioManagerTest, GetAudioOutputDeviceNames) {

[tommi (sloooow) - chröme, 2013/09/03 15:57:15]

What about putting this with the audiomanagerbase tests?  Seeing as all the
implementations derive from that class and the default implementation is there
(albeit not implemented), this would still "work".

[Jói, 2013/09/04 09:11:04]

There is no audio_manager_base_unittests.cc or any other file specifically for
AudioManager tests. Did you mean audio_input_device_unittest.cc? There are some
tests of AudioManager device enumeration there, so I could move them there if
you think that's better, let me know.

[tommi (sloooow) - chröme, 2013/09/04 10:48:11]

Sorry, what I was looking at were the platform specific test files. I think it's
a good idea to add this file and start having cross platform tests for the audio
manager (I thought we had those already but apparently we don't!).

+  AudioDeviceNames device_names;
+  audio_manager_->GetAudioOutputDeviceNames(&device_names);
+
+  VLOG(2) << "Got " << device_names.size() << " audio output devices.";
+  for (AudioDeviceNames::iterator it = device_names.begin();
+       it != device_names.end();
+       ++it) {
+    VLOG(2) << "Device ID(" << it->unique_id << "), label: " << it->device_name;

[tommi (sloooow) - chröme, 2013/09/03 15:57:15]

expect neither to be empty?

[Jói, 2013/09/04 09:11:04]

Done.

+  }
+}
+#endif  // defined(USE_PULSEAUDIO)
+
+}  // namespace media