Set connected OSU network to active AP at top of wifi picker

Clicking on an OSU network in the wifi picker should result in
the OSU network properly showing at the top as the connected
network instead of the underlying infrastructure AP.

Tracking bug for adding robolectric tests: b/122849296

Bug: 118705403
Test: manual, build and visual check
Change-Id: I05560b07acffb8aa85ac371d613088d5b7cd19f6