Switch WebRTC internal usage of FakeAudioDevice on TestAudioDeviceModule. Bug: webrtc:8946 Change-Id: I96b8b5d3b475d2197662e9007f836bd71f8ed04d Reviewed-on: https://webrtc-review.googlesource.com/60521 Reviewed-by: Karl Wiberg <kwiberg@webrtc.org> Commit-Queue: Artem Titov <titovartem@webrtc.org> Cr-Commit-Position: refs/heads/master@{#22388}