Re-land "Add a media constraint to enable beamforming"

content/renderer/media/media_stream_audio_processor_options.h

 // Copyright 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 CONTENT_RENDERER_MEDIA_MEDIA_STREAM_AUDIO_PROCESSOR_OPTIONS_H_
 #define CONTENT_RENDERER_MEDIA_MEDIA_STREAM_AUDIO_PROCESSOR_OPTIONS_H_
 
 #include <string>
 
 #include "base/files/file.h"
@@ skipping 23 matching lines @@
 class CONTENT_EXPORT MediaAudioConstraints {
  public:
   // Constraint keys used by audio processing.
   static const char kEchoCancellation[];
   static const char kGoogEchoCancellation[];
   static const char kGoogExperimentalEchoCancellation[];
   static const char kGoogAutoGainControl[];
   static const char kGoogExperimentalAutoGainControl[];
   static const char kGoogNoiseSuppression[];
   static const char kGoogExperimentalNoiseSuppression[];
+  static const char kGoogBeamforming[];
   static const char kGoogHighpassFilter[];
   static const char kGoogTypingNoiseDetection[];
   static const char kGoogAudioMirroring[];
 
   // Merge |constraints| with |kDefaultAudioConstraints|. For any key which
   // exists in both, the value from |constraints| is maintained, including its
   // mandatory/optional status. New values from |kDefaultAudioConstraints| will
   // be added with optional status.
   static void ApplyFixedAudioConstraints(RTCMediaConstraints* constraints);
 
@@ skipping 77 matching lines @@
 void StopEchoCancellationDump(AudioProcessing* audio_processing);
 
 void EnableAutomaticGainControl(AudioProcessing* audio_processing);
 
 void GetAecStats(AudioProcessing* audio_processing,
                  webrtc::AudioProcessorInterface::AudioProcessorStats* stats);
 
 }  // namespace content
 
 #endif  // CONTENT_RENDERER_MEDIA_MEDIA_STREAM_AUDIO_PROCESSOR_OPTIONS_H_