Revert of Revert of Remove the last piece of deprecated synchronous IO code.

content/renderer/media/webaudio_capturer_source.cc

Index: content/renderer/media/webaudio_capturer_source.cc
diff --git a/content/renderer/media/webaudio_capturer_source.cc b/content/renderer/media/webaudio_capturer_source.cc
index 7076c24f329ce8ff592d270f44a49fbca5144212..2095ac68f8cd1d1658ce3568c0362eb22554ee4f 100644
--- a/content/renderer/media/webaudio_capturer_source.cc
+++ b/content/renderer/media/webaudio_capturer_source.cc
@@ -48,7 +48,7 @@
   // as buffer size since that is the native buffer size of WebRtc packet
   // running on.
   params_.Reset(media::AudioParameters::AUDIO_PCM_LOW_LATENCY,
-                channel_layout, number_of_channels, 0, sample_rate, 16,
+                channel_layout, number_of_channels, sample_rate, 16,
                 sample_rate / 100);
   audio_format_changed_ = true;