Merge "Add test method...

Merge "Add test method UserLifecycleStressTest.switchToExistingGuestAndStartOverStressTest" into tm-dev am: e1062bc7 am: 52783a4d am: 932d04a2 am: 9013933a

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/17749723



Change-Id: I9fc0d781047f849c13034df9f59e90b1c697db6e
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>