Merge "Exclude a private display from getDisplayIdsForStartingVisibleBackgroundUsers" into udc-qpr-dev am: c6308f4df4 am: 8a3013cda4

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/23493421

Change-Id: I6ed5b5250b717757a88b65e7412009585e6dd39c
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>