fb: make battery light multiuser configurable

Change-Id: Ife6e72fef8da08d287b0790b0dda0fa3bb50c815
fb: small observer multiuser correction on notificationlight

Change-Id: I3bbe4c772f801e3edfc97f9e17000b03c861dd1f
fb: fix some missing hides

Change-Id: Ic4fe9a816092b20c4eb00e9fc75a8344fb21d236