- Move PreferenceGroup init method out of isAvailable() condition,
then PreferenceGroup will not be null.
- Update getAvailabilityStatus(), since the controller now may have usb
and dock.
Bug: 110712414
Test: make -j42 RunSettingsRoboTests
Change-Id: I4d85a42c26fb20d319e7321177b271933be3fdb0