Add support for audio input mute detection on all platforms

media/audio/mac/audio_input_mac.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_MAC_AUDIO_INPUT_MAC_H_
 #define MEDIA_AUDIO_MAC_AUDIO_INPUT_MAC_H_
 
 #include <AudioToolbox/AudioFormat.h>
 #include <AudioToolbox/AudioQueue.h>
 
@@ skipping 20 matching lines @@
   // Implementation of AudioInputStream.
   virtual bool Open() override;
   virtual void Start(AudioInputCallback* callback) override;
   virtual void Stop() override;
   virtual void Close() override;
   virtual double GetMaxVolume() override;
   virtual void SetVolume(double volume) override;
   virtual double GetVolume() override;
   virtual void SetAutomaticGainControl(bool enabled) override;
   virtual bool GetAutomaticGainControl() override;
+  virtual bool IsMuted() override;
 
  private:
   // Issue the OnError to |callback_|;
   void HandleError(OSStatus err);
 
   // Allocates and prepares the memory that will be used for recording.
   bool SetupBuffers();
 
   // Sends a buffer to the audio driver for recording.
   OSStatus QueueNextBuffer(AudioQueueBufferRef audio_buffer);
@@ skipping 34 matching lines @@
   base::CancelableClosure deferred_start_cb_;
 
   scoped_ptr<media::AudioBus> audio_bus_;
 
   DISALLOW_COPY_AND_ASSIGN(PCMQueueInAudioInputStream);
 };
 
 }  // namespace media
 
 #endif  // MEDIA_AUDIO_MAC_AUDIO_INPUT_MAC_H_