Merge "Allow alternateBouncer if at least once source has ui available" into...

Merge "Allow alternateBouncer if at least once source has ui available" into udc-qpr-dev am: cadad8e4 am: b218b301

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/24326998



Change-Id: I4bb3d6d20f378279fbc630f68436981b9b55afab
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>