Add removeListener, update tests, hide binder

Add a removeListener method to allow deregistration of interest in
config changes, update tests. Also, hide binder interfaces on the
android.app methods.

Test: Treehugger / atest of touched test files
Bug: 149014708
Bug: 159888952
Change-Id: Ic1a14c34334eb276724d97c4e763360d51cb035b