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

chromeos/audio/audio_pref_handler.h

+// Copyright (c) 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.
+
+#ifndef CHROMEOS_AUDIO_AUDIO_PREF_HANDLER_H_
+#define CHROMEOS_AUDIO_AUDIO_PREF_HANDLER_H_
+
+#include "base/basictypes.h"
+#include "base/memory/ref_counted.h"
+#include "chromeos/audio/audio_pref_observer.h"
+#include "chromeos/chromeos_export.h"
+
+class PrefRegistrySimple;
+
+namespace chromeos {
+
+// Interface that handles audio preference related work, reads and writes
+// audio preferences, and notifies AudioPrefObserver for audio preference
+// changes.
+class CHROMEOS_EXPORT AudioPrefHandler
+    : public base::RefCountedThreadSafe<AudioPrefHandler> {
+ public:
+  // Gets the audio output volume value from prefs.
+  virtual double GetOutputVolumeValue() = 0;
+
+  // Sets the output audio volume value to prefs.
+  virtual void SetOutputVolumeValue(double volume_percent) = 0;
+
+  // Reads the audio output mute value from prefs.
+  virtual bool GetOutputMuteValue() = 0;
+
+  // Sets the audio output mute value to prefs.
+  virtual void SetOutputMuteValue(bool mute_on) = 0;
+
+  // Reads the audio capture allowed value from prefs.
+  virtual bool GetAudioCaptureAllowedValue() = 0;
+
+  // Sets the audio output allowed value from prefs.
+  virtual bool GetAudioOutputAllowedValue() = 0;
+
+  // Adds an audio preference observer.
+  virtual void AddAudioPrefObserver(AudioPrefObserver* observer) = 0;
+
+  // Removes an audio preference observer.
+  virtual void RemoveAudioPrefObserver(AudioPrefObserver* observer) = 0;
+
+  // Creates the instance.
+  static AudioPrefHandler* Create(PrefService* local_state);
+
+ protected:
+  virtual ~AudioPrefHandler() {}
+
+ private:
+  friend class base::RefCountedThreadSafe<AudioPrefHandler>;
+};
+
+}  // namespace chromeos
+
+#endif  // CHROMEOS_AUDIO_AUDIO_PREF_HANDLER_H_