Merge "Merge "[User Switcher] Set default value if setting null." into...

Merge "Merge "[User Switcher] Set default value if setting null." into tm-qpr-dev am: 37cd9ae8" into tm-qpr-dev-plus-aosp am: cae70fbf

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/20583477



Change-Id: I3047b906534216965f38b189569443063dad116c
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>