Fix the audio mute button broken issue.

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 87 matching lines @@
 
   // Returns true if audio output is muted for a device.
   virtual bool IsOutputMutedForDevice(uint64 device_id);
 
   // Returns true if audio input is muted.
   virtual bool IsInputMuted();
 
   // Returns true if audio input is muted for a device.
   virtual bool IsInputMutedForDevice(uint64 device_id);
 
+  // Returns true if the output volume is below the default mute volume level.
+  virtual bool IsOutputVolumeBelowDefaultMuteLvel();
+
   // Gets volume level in 0-100% range (0 being pure silence) for the current
   // active node.
   virtual int GetOutputVolumePercent();
 
   // Gets volume level in 0-100% range (0 being pure silence) for a device.
   virtual int GetOutputVolumePercentForDevice(uint64 device_id);
 
   // Gets gain level in 0-100% range (0 being pure silence) for the current
   // active node.
   virtual int GetInputGainPercent();
@@ skipping 20 matching lines @@
   // mutes the sound. If it was muted, and |volume_percent| is larger than
   // the threshold, then the sound is unmuted.
   virtual void SetOutputVolumePercent(int volume_percent);
 
   // Sets gain level 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);
 
   // Mutes or unmutes audio input device.
   virtual void SetInputMute(bool mute_on);
 
   // Sets the active audio output node to the node with |node_id|.
   virtual void SetActiveOutputNode(uint64 node_id);
 
   // Sets the active audio input node to the node with |node_id|.
@@ skipping 33 matching lines @@
   // is created or cras audio client is restarted.
   void InitializeAudioState();
 
   // Applies the audio muting policies whenever the user logs in or policy
   // change notification is received.
   void ApplyAudioPolicy();
 
   // Sets output volume to specified value of |volume|.
   void SetOutputVolumeInternal(int volume);
 
-  // Sets output mute state to |mute_on|.
+  // Sets output mute state to |mute_on| internally, returns true if output mute
+  // is set.
   bool SetOutputMuteInternal(bool mute_on);
 
   // Sets output volume to specified value and notifies observers.
   void SetInputGainInternal(int gain);
 
+  // Sets input mute state to |mute_on| internally, returns true if input mute
+  // is set.
+  bool SetInputMuteInternal(bool mute_on);
+
   // Calling dbus to get nodes data.
   void GetNodes();
 
   // Updates the current audio nodes list and switches the active device
   // if needed.
   void UpdateDevicesAndSwitchActive(const AudioNodeList& nodes);
 
   void SwitchToDevice(const AudioDevice& device);
 
   // Handles dbus callback for GetNodes.
@@ skipping 20 matching lines @@
 
   bool output_mute_locked_;
   bool input_mute_locked_;
 
   DISALLOW_COPY_AND_ASSIGN(CrasAudioHandler);
 };
 
 }  // namespace chromeos
 
 #endif  // CHROMEOS_AUDIO_CRAS_AUDIO_HANDLER_H_