Prevent unintentional removal of widgets pinned by another host

appWidgetIds are only unique within the same user, which could lead to overlaps in HSUM. This CL prevents a host from accessing widgets hosted by a entirely different package. (A host can still access widgets hosted by the same package but running in different user if it has interact across users permission)

Bug: 386303131
Test: manual
Flag: EXEMPT bugfix
Change-Id: Ibd08307118af3fdc22ec57668af82213bce576b7