Add a new audio constraint, 'googHotword', that requests the hotword input

content/renderer/media/media_stream_audio_processor_options.cc

 // 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.
 
 #include "content/renderer/media/media_stream_audio_processor_options.h"
 
 #include "base/files/file_path.h"
 #include "base/files/file_util.h"
 #include "base/logging.h"
 #include "base/metrics/field_trial.h"
@@ skipping 49 matching lines @@
   { MediaAudioConstraints::kGoogExperimentalAutoGainControl, true },
   { MediaAudioConstraints::kGoogNoiseSuppression, true },
   { MediaAudioConstraints::kGoogHighpassFilter, true },
   { MediaAudioConstraints::kGoogTypingNoiseDetection, true },
   { MediaAudioConstraints::kGoogExperimentalNoiseSuppression, false },
 #if defined(OS_WIN)
   { kMediaStreamAudioDucking, true },
 #else
   { kMediaStreamAudioDucking, false },
 #endif
+  { kMediaStreamAudioHotword, false },
 };
 
 bool IsAudioProcessingConstraint(const std::string& key) {
   // |kMediaStreamAudioDucking| does not require audio processing.
   return key != kMediaStreamAudioDucking;
 }
 
 // Used to log echo quality based on delay estimates.
 enum DelayBasedEchoQuality {
   DELAY_BASED_ECHO_QUALITY_GOOD = 0,
@@ skipping 287 matching lines @@
   }
 
   int median = 0, std = 0;
   if (!audio_processing->echo_cancellation()->GetDelayMetrics(&median, &std)) {
     stats->echo_delay_median_ms = median;
     stats->echo_delay_std_ms = std;
   }
 }
 
 }  // namespace content