Merge "Add migration indication area feature flag" into udc-dev am: fe5a1dc8 am: 0da8b900 am: 75072fad am: 0c23026f

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/23134078



Change-Id: I43643635bbf2cb5ad1a35a45e9054746e4ee179f
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>