The functionality is moved into AudioState. TBR: henrika@webrtc.org Bug: webrtc:4690 Change-Id: I015482ad18a39609634f6ead9e991d5210107f0f Reviewed-on: https://webrtc-review.googlesource.com/34502 Reviewed-by: Fredrik Solenberg <solenberg@webrtc.org> Commit-Queue: Fredrik Solenberg <solenberg@webrtc.org> Cr-Commit-Position: refs/heads/master@{#21338}