Merge "Allows a plugin Settings activity to designate plugins it supports." into sc-dev am: ad1d1cfda0

Original change: https://googleplex-android-review.googlesource.com/c/platform/packages/apps/Launcher3/+/13452494

MUST ONLY BE SUBMITTED BY AUTOMERGER

Change-Id: Ic3a7da84ed262bd9d860328a5d93eecd23823fbe