Merge "Fix stalled background thread bug" into udc-dev am: b739e148

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/23765836



Change-Id: Ic1c1623c86d405e8a83f7e984e143062f721146b
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>