Merge "Fix stalled background thread bug" into udc-dev am: b739e148 am: 9dfb3186 am: 479add1f

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



Change-Id: Ifa18af1dead416851249b712263d88555bb03d60
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>