Remove unused code for ApplyFixedAudioConstraints in media_stream_audio_processor.

content/renderer/media/media_stream_audio_processor_options.cc

Index: content/renderer/media/media_stream_audio_processor_options.cc
diff --git a/content/renderer/media/media_stream_audio_processor_options.cc b/content/renderer/media/media_stream_audio_processor_options.cc
index 7c1c929d251612d8e6e3b5967887bb2b148b14ee..73e2b51aeb1a7761efd4d29c7d0e1e162aa4f309 100644
--- a/content/renderer/media/media_stream_audio_processor_options.cc
+++ b/content/renderer/media/media_stream_audio_processor_options.cc
@@ -134,32 +134,8 @@ bool ScanConstraintsForBoolean(
   return the_default;
 }
 
-void SetIfNotSet(rtc::Optional<bool>* field, bool value) {
-  if (!*field) {
-    *field = rtc::Optional<bool>(value);
-  }
-}
-
 }  // namespace
 
-// TODO(xians): Remove this method after the APM in WebRtc is deprecated.
-void MediaAudioConstraints::ApplyFixedAudioConstraints(
-    cricket::AudioOptions* options) {
-  SetIfNotSet(&options->echo_cancellation, true);
-#if defined(OS_ANDROID)
-  SetIfNotSet(&options->extended_filter_aec, false);
-#else
-  // Enable the extended filter mode AEC on all non-mobile platforms.
-  SetIfNotSet(&options->extended_filter_aec, true);
-#endif
-  SetIfNotSet(&options->auto_gain_control, true);
-  SetIfNotSet(&options->experimental_agc, true);
-  SetIfNotSet(&options->noise_suppression, true);
-  SetIfNotSet(&options->highpass_filter, true);
-  SetIfNotSet(&options->typing_detection, true);
-  SetIfNotSet(&options->experimental_ns, true);
-}
-
 MediaAudioConstraints::MediaAudioConstraints(
     const blink::WebMediaConstraints& constraints, int effects)
     : constraints_(constraints),