Merge "Better diagnosing leaked activities." into sc-dev am: 161b27d5c5

Original change: https://googleplex-android-review.googlesource.com/c/platform/packages/apps/Launcher3/+/13714586

MUST ONLY BE SUBMITTED BY AUTOMERGER

Change-Id: Id9c0166413ff2e39ed0e3905d550a417cbd7387c