All of WebRTC's mb_configs should have been swapped over to using
'builder_groups'.
Bug: chromium:1117773, webrtc:11680
Change-Id: I5509c242ded0a381b781eef14c2514247eaedf1b
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/201721
Commit-Queue: Mirko Bonadei <mbonadei@webrtc.org>
Reviewed-by: Dirk Pranke <dpranke@google.com>
Cr-Commit-Position: refs/heads/master@{#32987}