Use scores from connected AP only.

When connected to a specific base station, show the speed label for that
specific access point, rather than the best label for all similar access
points in the area.

Bug: b/63073866
Test: runtest --path
frameworks/base/packages/SettingsLib/tests/integ/src/com/android/settingslib/wifi/AccessPointTest.java

Change-Id: Ic3b3c5838ca8b43daa226335125bb8046dee3884