This CL also fixes data races caused by tests themselves. TBR= henrika@webrtc.org Bug: webrtc:9751 Change-Id: Ie7c785b27142fd465f5b4dc9fb0628bd7274f1d2 Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/146600 Reviewed-by: Henrik Andreassson <henrika@webrtc.org> Commit-Queue: Yves Gerey <yvesg@google.com> Cr-Commit-Position: refs/heads/master@{#28829}