[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
2 files changed