Implement HasInputDevices in CrasAudioManager

media/audio/audio_manager.h

 // Copyright (c) 2012 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 MEDIA_AUDIO_AUDIO_MANAGER_H_
 #define MEDIA_AUDIO_AUDIO_MANAGER_H_
 
 #include <string>
 
 #include "base/basictypes.h"
@@ skipping 193 matching lines @@
   // Create a new AudioLog object for tracking the behavior for one or more
   // instances of the given component.  See AudioLogFactory for more details.
   virtual scoped_ptr<AudioLog> CreateAudioLog(
       AudioLogFactory::AudioComponent component) = 0;
 
   // Informs the audio manager that the system has support for a keyboard mic.
   // This information will be passed on in the return value of
   // GetInputStreamParameters as an effect. Only supported on ChromeOS.
   virtual void SetHasKeyboardMic() = 0;
 
+  // Informs the audio manager that the system has support for an input device.
+  // This information will be cached for HasAudioInputDevices.
+  // Only supported on ChromeOS.

[Daniel Erat, 2015/06/18 14:53:20]

nit: s/ChromeOS/Chrome OS/ (the product name has always had a space in it)

[cychiang, 2015/06/23 06:05:40]

Done.

+  virtual void SetHasInputDevices(bool has_input_devices) = 0;
+
  protected:
   AudioManager();
 
  private:
   DISALLOW_COPY_AND_ASSIGN(AudioManager);
 };
 
 }  // namespace media
 
 #endif  // MEDIA_AUDIO_AUDIO_MANAGER_H_