The code was doing nothing except for triggering thread sanitizer,
since concurrent writes weren't guarded:
* ReadRecordedData() through webrtc_audio_module_rec_thread
* InitPlayout() through main thread
Bug: webrtc:9751
Change-Id: I7ecf4fa436ff0695e5b998d7e3f159fb6c7e9214
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/146216
Reviewed-by: Henrik Andreassson <henrika@webrtc.org>
Commit-Queue: Yves Gerey <yvesg@google.com>
Cr-Commit-Position: refs/heads/master@{#28636}