[Wi-Fi] Fix SavedAccessPointsPreferenceController crash when editing Settings search box

In getAvailabilityStatus(), refresh mAccessPoints before using it.

Bug: 147096386
Test: make RunSettingsRoboTests ROBOTEST_FILTER=SavedAccessPointsPreferenceControllerTest
Change-Id: Id6818bd7bab1effb2e4e1447b18d5f5f02d7cfca

src/com/android/settings/wifi/savedaccesspoints/SavedAccessPointsPreferenceController.java

@@ -59,6 +59,7 @@ public class SavedAccessPointsPreferenceController extends BasePreferenceControl
 
     @Override
     public int getAvailabilityStatus() {
+        refreshSavedAccessPoints();
         return mAccessPoints.size() > 0 ? AVAILABLE : CONDITIONALLY_UNAVAILABLE;
     }