Reader-writer locks helps performance only when there are many concurrent readers, and I would expect that isn't the case for this class. Using a plain mutex reduces complexity. Bug: webrtc:12102 Change-Id: I07c315bcbfc38f1d8befe5395c9ece54c673aeb7 Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/190722 Reviewed-by: Magnus Flodman <mflodman@webrtc.org> Commit-Queue: Niels Moller <nisse@webrtc.org> Cr-Commit-Position: refs/heads/master@{#32547}