Enable new getUserMedia audio constraints algorithm behind a flag.

content/renderer/media/media_stream_audio_processor_options.h

Index: content/renderer/media/media_stream_audio_processor_options.h
diff --git a/content/renderer/media/media_stream_audio_processor_options.h b/content/renderer/media/media_stream_audio_processor_options.h
index c891c8c1c1ccb579e72ee453f4e4eefad9245fcb..153a26c57b3eee4b6cef1e6cadd90168f2921483 100644
--- a/content/renderer/media/media_stream_audio_processor_options.h
+++ b/content/renderer/media/media_stream_audio_processor_options.h
@@ -110,6 +110,14 @@ struct CONTENT_EXPORT AudioProcessingProperties {
   AudioProcessingProperties& operator=(AudioProcessingProperties&& other);
   ~AudioProcessingProperties();
 
+  // Disables properties that are enabled by default.
+  void DisableDefaultPropertiesForTesting();
+
+  // TODO(guidou): Remove this function. http://crbug.com/706408
+  static AudioProcessingProperties FromConstraints(
+      const blink::WebMediaConstraints& constraints,
+      const MediaStreamDevice::AudioDeviceParameters& input_params);
+
   bool enable_sw_echo_cancellation = true;
   bool disable_hw_echo_cancellation = false;
   bool goog_audio_mirroring = false;
@@ -197,10 +205,14 @@ void GetAudioProcessingStats(
 
 // Returns the array geometry from the media constraints if existing and
 // otherwise that provided by the input device.
-CONTENT_EXPORT std::vector<webrtc::Point> GetArrayGeometryPreferringConstraints(
+// TODO(guidou): Remove this function. http://crbug.com/706408
+CONTENT_EXPORT std::vector<media::Point> GetArrayGeometryPreferringConstraints(
     const MediaAudioConstraints& audio_constraints,
     const MediaStreamDevice::AudioDeviceParameters& input_params);
 
+// TODO(guidou): Remove this function. http://crbug.com/706408
+CONTENT_EXPORT bool IsOldAudioConstraints();
+
 }  // namespace content
 
 #endif  // CONTENT_RENDERER_MEDIA_MEDIA_STREAM_AUDIO_PROCESSOR_OPTIONS_H_