This class used only write locks, no read locks, and hence a plain mutex is equivalent. Bug: webrtc:12102 Change-Id: Ia3e52a5cb2db7679a50fca0ab80f85640876d0bd Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/190720 Reviewed-by: Jamie Walch <jamiewalch@chromium.org> Commit-Queue: Niels Moller <nisse@webrtc.org> Cr-Commit-Position: refs/heads/master@{#32539}