Merge "Add test method...

Merge "Add test method UserLifecycleStressTest.switchToExistingGuestAndStartOverStressTest" into tm-dev am: e1062bc7 am: b1c40b1e

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



Change-Id: I296f0d6f4408dea5551c80181e2d20e0d20f781c
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>