Merge "[User Switcher] remove add guest user..." into tm-qpr-dev am: e182b0d4 am: 6b6edeb6

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/20454380



Change-Id: I55163ef8c413fba54f48509759931510243eddb8
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>