Merge "Defuse notification race around app stops" into tm-dev am: 81ac10a9

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/18624638



Change-Id: I6adc06db3eed43b4e9e3f58c1f34adb33d054304
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>