Merge "Guard against the exceptions when launching a non-existing fragment"...

Merge "Guard against the exceptions when launching a non-existing fragment" into sc-dev am: 1f4eb8fb am: d24ee9c0

Original change: https://googleplex-android-review.googlesource.com/c/platform/packages/apps/Settings/+/15142234

Change-Id: I189c81e167c158a513bc4e0df8e9c4f039057ccb