Integrate audio dbus api: GetNodes.

chromeos/dbus/audio_node.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_DBUS_VOLUME_STATE_H_
-#define CHROMEOS_DBUS_VOLUME_STATE_H_
+#ifndef CHROMEOS_DBUS_AUDIO_NODE_H_
+#define CHROMEOS_DBUS_AUDIO_NODE_H_
 
 #include <string>
+#include <vector>
 
 #include "base/basictypes.h"
 #include "chromeos/chromeos_export.h"
 
 namespace chromeos {
 
-struct CHROMEOS_EXPORT VolumeState {
-  int32 output_volume;
-  bool output_mute;
-  int32 input_gain;
-  bool input_mute;
+struct CHROMEOS_EXPORT AudioNode {
+  bool is_input;
+  uint64 id;
+  std::string device_name;
+  std::string type;
+  std::string name;
+  bool active;
 
-  VolumeState();
+  AudioNode();
   std::string ToString() const;
 };
 
+typedef std::vector<AudioNode> AudioNodeList;
+
 }  // namespace chromeos
 
-#endif  // CHROMEOS_DBUS_VOLUME_STATE_H_
+#endif  // CHROMEOS_DBUS_AUDIO_NODE_H_