Add support for audio input mute detection on all platforms

media/audio/fake_audio_input_stream.cc

 // 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.
 
 #include "media/audio/fake_audio_input_stream.h"
 
 #include "base/bind.h"
 #include "base/lazy_instance.h"
 #include "media/audio/audio_manager_base.h"
 #include "media/base/audio_bus.h"
@@ skipping 185 matching lines @@
 
 void FakeAudioInputStream::SetVolume(double volume) {
   DCHECK(audio_manager_->GetTaskRunner()->BelongsToCurrentThread());
 }
 
 double FakeAudioInputStream::GetVolume() {
   DCHECK(audio_manager_->GetTaskRunner()->BelongsToCurrentThread());
   return 1.0;
 }
 
+bool FakeAudioInputStream::IsMuted() {
+  DCHECK(audio_manager_->GetTaskRunner()->BelongsToCurrentThread());
+  return false;
+}
+
 void FakeAudioInputStream::SetAutomaticGainControl(bool enabled) {}
 
 bool FakeAudioInputStream::GetAutomaticGainControl() {
   return true;
 }
 
 // static
 void FakeAudioInputStream::BeepOnce() {
   BeepContext* beep_context = g_beep_context.Pointer();
   beep_context->SetBeepOnce(true);
 }
 
 }  // namespace media