Implement two new policies to control muting the audio I/O.

chrome/browser/chromeos/audio/audio_mixer_cras.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 CHROME_BROWSER_CHROMEOS_AUDIO_AUDIO_MIXER_CRAS_H_
 #define CHROME_BROWSER_CHROMEOS_AUDIO_AUDIO_MIXER_CRAS_H_
 
 #include <cras_client.h>
 
 #include "base/basictypes.h"
@@ skipping 11 matching lines @@
 class AudioMixerCras : public AudioMixer {
  public:
   AudioMixerCras();
   virtual ~AudioMixerCras();
 
   // AudioMixer implementation.
   virtual void Init() OVERRIDE;
   virtual double GetVolumePercent() OVERRIDE;
   virtual void SetVolumePercent(double percent) OVERRIDE;
   virtual bool IsMuted() OVERRIDE;
-  virtual void SetMuted(bool muted) OVERRIDE;
+  virtual void SetMuted(bool mute) OVERRIDE;
+  virtual bool IsMuteLocked() OVERRIDE;
+  virtual void SetMuteLocked(bool locked) OVERRIDE;
+  virtual bool IsCaptureMuted() OVERRIDE;
+  virtual void SetCaptureMuted(bool mute) OVERRIDE;
+  virtual bool IsCaptureMuteLocked() OVERRIDE;
+  virtual void SetCaptureMuteLocked(bool locked) OVERRIDE;
 
  private:
   // Tries to connect to CRAS.  On failure, posts a delayed Connect() task to
   // try again.  Failure could occur if the CRAS server isn't running yet.
   void Connect();
 
   // Updates |client_| for current values of |volume_percent_| and
   // |is_muted_|. No-op if not connected.
   void ApplyState();
 
+  // Calls ApplyState on the proper thread only if no other call is currently
+  // pending.
+  void ApplyStateIfNeeded();
+
   // Interfaces to the audio server.
   struct cras_client *client_;
 
   // Indicates if we have connected |client_| to the server.
   bool client_connected_;
 
   // Most recently-requested volume, in percent.  This variable is updated
   // immediately by SetVolumePercent() (post-initialization); the actual mixer
   // volume is updated later on |thread_| by ApplyState().
   double volume_percent_;
 
   // Most recently-requested muting state.
   bool is_muted_;
+  bool is_mute_locked_;
+  bool is_capture_muted_;
+  bool is_capture_mute_locked_;
 
   // Is there already a pending call to ApplyState() scheduled on |thread_|?
   bool apply_is_pending_;
 
   // Background thread used for interacting with CRAS.
   scoped_ptr<base::Thread> thread_;
 
-  // Guards |volume_percent_|, |is_muted_|, and |apply_is_pending_|.
+  // Guards |volume_percent_|, |is_muted_|, |is_mute_locked_|,
+  // |is_capture_muted_|, |is_capture_mute_locked_|, and |apply_is_pending_|.
   base::Lock lock_;
 
   DISALLOW_COPY_AND_ASSIGN(AudioMixerCras);
 };
 
 }  // namespace chromeos
 
 #endif  // CHROME_BROWSER_CHROMEOS_AUDIO_AUDIO_MIXER_CRAS_H_