Update AppOps & UsageStats when app widget tapped.

When the app widget on the launcher is tapped on:
1. Update AppOps. AppOps treats the underlying app as foreground so the app can get while-in-use
permission.
2. Report a USER_INTERACTION event to UsageStats so UsageStats can
update mLastTimeUsed and mLastTimeVisible of this package.

Bug: 149043079
Test: manual test, tapped on a widget.
Change-Id: Ic8c91190881cf5dcf89f0f72cfd410b0c2e86bf6