Attempt to fix FixedQueue.ConcurrentPushPopWithResize flakiness If dequeueThread has finished while the enqueue thread is sleeping, queue might still be full once enqueueThread wakes up. In this case, push call will hit assertion since queue is full. This CL makes the enqueueThread bail out if dequeueThread already finished. Bug: chromium:1493831 Change-Id: I9e3ad957c5d2eb15c5b409bb818c03dc807f3518 Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/4957194 Reviewed-by: Yuxin Hu <yuxinhu@google.com> Commit-Queue: Charlie Lao <cclao@google.com>