Merge "Fullscreen user switching dialog with animations." into udc-dev am:...

Merge "Fullscreen user switching dialog with animations." into udc-dev am: 0110ea13 am: 586defc8

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/22336265



Change-Id: I6faecbd55c992b8930a7b991abe994f2bf08907d
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>