Use WifiPickerTracker to get connected WifiEntry

Use WifiPickerTracker.getConnectedWifiEntry API to get a WifiEntry to
display at the top of the Wifi picker as the connected network.

Test: manual - visual verification of connected entry at the top of the
wifi picker.
Bug: 70983952

Change-Id: Iec6e1c9fe950397f62350194d8b24791a7eac30a
1 file changed