Merge "Move widget files into widget folder + add tests." into sc-dev am: a6554759aa

Original change: https://googleplex-android-review.googlesource.com/c/platform/packages/apps/Launcher3/+/13661706

MUST ONLY BE SUBMITTED BY AUTOMERGER

Change-Id: I70c3d7bb2a2be70807dee46867ad92e2d827b992