Merge "Diagnosing when only SysUI is visible." into sc-v2-dev am: 2be25906

Original change: https://googleplex-android-review.googlesource.com/c/platform/packages/apps/Launcher3/+/15375786

Change-Id: I988b5e0876ed6a37c88c4dccb9e2afc7825d847c