Add test coverage for CrasAudioHandler.

chromeos/audio/cras_audio_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_CRAS_AUDIO_HANDLER_H_
 #define CHROMEOS_AUDIO_CRAS_AUDIO_HANDLER_H_
 
 #include <queue>
 
 #include "base/basictypes.h"
@@ skipping 119 matching lines @@
 
   // Gets the audio devices back in |device_list|.
   virtual void GetAudioDevices(AudioDeviceList* device_list) const;
 
   virtual bool GetActiveOutputDevice(AudioDevice* device) const;
 
   // Whether there is alternative input/output audio device.
   virtual bool has_alternative_input() const;
   virtual bool has_alternative_output() const;
 
-  // Sets volume level from 0-100%. If less than kMuteThresholdPercent, then
-  // mutes the sound. If it was muted, and |volume_percent| is larger than
-  // the threshold, then the sound is unmuted.
+  // Sets volume level to |volume_percent|, whose range is from 0-100%.
   virtual void SetOutputVolumePercent(int volume_percent);
 
-  // Sets gain level from 0-100%.
+  // Sets gain level to |gain_percent|, whose range is from 0-100%.
   virtual void SetInputGainPercent(int gain_percent);
 
   // Adjusts volume up (positive percentage) or down (negative percentage).
   virtual void AdjustOutputVolumeByPercent(int adjust_by_percent);
 
   // Adjusts output volume to a minimum audible level if it is too low.
   virtual void AdjustOutputVolumeToAudibleLevel();
 
   // Mutes or unmutes audio output device.
   virtual void SetOutputMute(bool mute_on);
@@ skipping 96 matching lines @@
 
   bool output_mute_locked_;
   bool input_mute_locked_;
 
   DISALLOW_COPY_AND_ASSIGN(CrasAudioHandler);
 };
 
 }  // namespace chromeos
 
 #endif  // CHROMEOS_AUDIO_CRAS_AUDIO_HANDLER_H_