Fix persistent dot not removed due to race condition in scheduler

Bug: 300741186
Test: atest SystemStatusAnimationSchedulerImplTest
(cherry picked from https://googleplex-android-review.googlesource.com/q/commit:d027036adf637b5db0f119afef5218b6a8ce37af)
Merged-In: I7380cb956b48c38bdd540b297287786cf35b94f2
Change-Id: I7380cb956b48c38bdd540b297287786cf35b94f2
2 files changed