Merge "[Bouncer] Add bouncer feature flag." into tm-qpr-dev am: 8b1afeb3

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/19504868



Change-Id: I631ffa797652df295ae9b5810468414113637fd9
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>