Merge "Fix stalled background thread bug" into udc-dev am: b739e148 am: b2c86ab0 am: feb71c3f

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



Change-Id: I953f6216f2616e50b079797e50b4db16c4a2220d
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>