Merge "Remove stopped activity from UnknownAppVisibilityController." into sc-dev am: 33dfa744 am: 8d7e1c5e

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/15114538

Change-Id: I066b60342caff02106ac72d9849f80b94d35976f