Added initial OsuProvider support for AccessPoint and WifiTracker

AccessPoint entries representing OSU providers should now appear
in the wifi picker with their titles set to their OSU friendly name.
Tapping on these entries will yield unexpected behavior for now, as
the provisioning action has not been implemented yet. The RSSI has
been set to an arbitrary value until these entries can be matched to
their scan results. All available OSU providers will appear until a
further CL removes entries for networks that have already been
provisioned for.

Tracking bug for adding robolectric tests: b/122849296

Test: manual, build and visual check
Bug: 118705403
Change-Id: I30f61ae83100f80dab422ad742f23c32cdd2079a