Switch Chromium code over to new voice detection API.

This CL removes all Chromium dependencies on the to-be-removed
webrtc::AudioProcessing::voice_detection() interface.

Bug: webrtc:9947
Change-Id: Ic81fd8b1f79a4f52be27c18b66ba29ca38878a2c
Reviewed-on: https://chromium-review.googlesource.com/c/1394527
Reviewed-by: Oskar Sundbom <ossu@chromium.org>
Reviewed-by: Max Morin <maxmorin@chromium.org>
Commit-Queue: Sam Zackrisson <saza@chromium.org>
Cr-Commit-Position: refs/heads/master@{#620353}
5 files changed