Instead stop/delete TaskQueueBase in destructor explicitly and explain potential race. Bug: webrtc:14169 Change-Id: Ica7a78f149be11ba1a82cbf79d4244c918aa9d0a Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/335360 Reviewed-by: Tomas Gunnarsson <tommi@webrtc.org> Commit-Queue: Danil Chapovalov <danilchap@webrtc.org> Cr-Commit-Position: refs/heads/main@{#41810}