Add getA11yPackageNames() into SettingsLib for other modules

Bug: 175521403
Bug: 306329984
Test: make RunSettingsLibRoboTests -j40 ROBOTEST_FILTER="com.android.settingslib.fuelgauge"
Change-Id: I10c6edf9f217b468808c6e028e912b319137ac4e
2 files changed