Integrate audio dbus api: GetNodes.

chromeos/dbus/cras_audio_client.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_CRAS_AUDIO_CLIENT_H_
 #define CHROMEOS_DBUS_CRAS_AUDIO_CLIENT_H_
 
 #include "base/callback.h"
 #include "base/observer_list.h"
 #include "chromeos/chromeos_export.h"
+#include "chromeos/dbus/audio_node.h"
 #include "chromeos/dbus/dbus_client_implementation_type.h"
 #include "chromeos/dbus/volume_state.h"
 
 namespace dbus {
 class Bus;
 }  // namespace
 
 namespace chromeos {
 
 // CrasAudioClient is used to communicate with the cras audio dbus interface.
@@ skipping 17 matching lines @@
 
   virtual ~CrasAudioClient();
 
   // Adds and removes the observer.
   virtual void AddObserver(Observer* observer) = 0;
   virtual void RemoveObserver(Observer* observer) = 0;
   // Returns true if this object has the given observer.
   virtual bool HasObserver(Observer* observer) = 0;
 
   // GetVolumeStateCallback is used for GetVolumeState method. It receives
-  // 1 argument, |volume_state| which containing both input and  output volume
-  // state data.
-  typedef base::Callback<void(const VolumeState&)> GetVolumeStateCallback;
+  // 2 arguments, |volume_state| which containing both input and  output volume
+  // state data, and |success| which indicates whether or not the request
+  // succeeded.
+  typedef base::Callback<void(const VolumeState&, bool)> GetVolumeStateCallback;
+
+  // GetNodesCallback is used for GetNodes method. It receives 2 arguments,
+  // |audio_nodes| which containing a list of audio nodes data and
+  // |success| which indicates whether or not the request succeeded.
+  typedef base::Callback<void(const AudioNodeList&, bool)> GetNodesCallback;
 
   // Gets the volume state, asynchronously.
   virtual void GetVolumeState(const GetVolumeStateCallback& callback) = 0;
 
+  // Gets an array of audio input and output nodes.
+  virtual void GetNodes(const GetNodesCallback& callback) = 0;
+
   // Sets output volume to |volume|, in the range of [0, 100].
   virtual void  SetOutputVolume(int32 volume) = 0;
 
   // Sets output mute state to |mute_on| value.
   virtual void SetOutputMute(bool mute_on) = 0;
 
   // Sets input gain to |input_gain|. |input_gain| is specified in dBFS * 100.
   virtual void SetInputGain(int32 input_gain) = 0;
 
   // Sets input mute state to |mute_on| value.
@@ skipping 14 matching lines @@
   CrasAudioClient();
 
  private:
 
   DISALLOW_COPY_AND_ASSIGN(CrasAudioClient);
 };
 
 }  // namespace chromeos
 
 #endif  // CHROMEOS_DBUS_CRAS_AUDIO_CLIENT_H_