Implement new audio handler which talks to the new audio dbus apis.

chromeos/audio/audio_pref_names.cc

Index: chromeos/audio/audio_pref_names.cc
diff --git a/chromeos/audio/audio_pref_names.cc b/chromeos/audio/audio_pref_names.cc
new file mode 100644
index 0000000000000000000000000000000000000000..92b140e965ab5e440bb51ff853afc34e07ab95c3
--- /dev/null
+++ b/chromeos/audio/audio_pref_names.cc
@@ -0,0 +1,33 @@
+// 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 "chromeos/audio/audio_pref_names.h"
+
+namespace chromeos {
+
+namespace prefs {
+
+// TODO(jennyz): crbug.com/160311. Remove the same prefs from
+// chrome/common/pref_names.cc, once we retire the old AudioHandler code.

[stevenjb, 2013/04/17 01:25:12]

Does it make sense to change the old code to include this file instead?

[jennyz, 2013/04/18 01:21:19]

It turns out that one of the audio pref, ie, kAudioCaptureAllowed is not
chromeos only, which is used by chrome in other places too. I end up with
refactoring all the pref related code to AudioPrefHandler and pass this object
into both old and new audio handlers. Please take a look.

+
+// A pref holding the value of the policy used to disable capturing audio on
+// ChromeOS devices.
+const char kAudioCaptureAllowed[] = "hardware.audio_capture_enabled";
+
+// An integer pref to initially mute volume if 1. This pref is ignored if
+// |kAudioOutputAllowed| is set to false, but its value is preserved, therefore
+// when the policy is lifted the original mute state is restored.
+const char kAudioMute[] = "settings.audio.mute";
+
+// A pref holding the value of the policy used to disable playing audio on
+// ChromeOS devices. This pref overrides |kAudioMute| but does not overwrite
+// it, therefore when the policy is lifted the original mute state is restored.
+const char kAudioOutputAllowed[] = "hardware.audio_output_enabled";
+
+// A double pref storing the user-requested volume.
+const char kAudioVolumePercent[] = "settings.audio.volume_percent";
+
+}  // namespace prefs
+
+}  // namespace chromeos