Now that voe::Channel is owned by Audio[Send|Receive]Stream, the legacy
VoiceEngine and the VoEBase interface is unused.
Also removes Atomic32, which was only used for ref counting VoiceEngine.
Bug: webrtc:4690
Change-Id: I73b8a083df544a8ab6383d57075a65ce955c592a
Reviewed-on: https://webrtc-review.googlesource.com/38723
Commit-Queue: Fredrik Solenberg <solenberg@webrtc.org>
Reviewed-by: Henrik Andreassson <henrika@webrtc.org>
Reviewed-by: Karl Wiberg <kwiberg@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#21595}