[WifiNetworkSelector] Don't discard scan results if current network is poor

This uses the connected score to decide whether it is OK for the current
bssid to be absent from the scan results. Otherwise we can stay stuck on
a very poor network even though a better choice is available.

Bug: 122102717
Test: ./frameworks/opt/net/wifi/tests/wifitests/runtests.sh
Test: ACTS test_network_selector_5g_to_2g_same_ssid
Test: ACTS test_autojoin_Ap1_5gto2g_AP1_10_AP2_80_AP3_95

Change-Id: I7aaf307fdc5b596b6bef49482d9896c7b34e6dad
1 file changed