Do not show unreachable APs in QS Wifi Picker.

This consolidates logic between the QS Picker and the WifiSettings
Picker. Previous QS behavior would show the out of range networks with
empty wifi pies, can last up to 3 scans, and differs from behavior in
WifiSettings.

Bug: b/62680006
Test: 1. Open the quick settings picker
  2. Minimize the picker
  3. Walk out of range of the networks you say listed in the picker
  4. Re-open picker
  5. Networks should not be shown.

Change-Id: Ic042f3e6ac41b426c343ccca288b26dcaaafa7fb