Merge "Do not throw exception on task vanished" into tm-qpr-dev am: e572351d

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/22333702



Change-Id: I87e7bebe150197eb81d4bd886cbbcf94bfed1ad7
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>