Merge "User Switcher: Prevent flickering for user switch." into tm-dev am:...

Merge "User Switcher: Prevent flickering for user switch." into tm-dev am: f1393850 am: 5f446b2d

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/17260686



Change-Id: I183a4cf1152bc758a8584fccb6ed693d2fdbcfc4
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>