Merge "Make flushing broadcast loopers optional." into udc-dev am: 3e7d7d63

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/23224746



Change-Id: If2b9a6df933c2806348543dbb28d80d18b8aba00
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>