If I didn't miss anything these are indeed not used. Old themes should still work (will only print info on redundant theme defines into console), but updated non-contrib themes already.
Had to fix it by hand (restting them to default values), theme maintainers,
please check your theme from time to time and track such ugly 'pitch black' fields.
And we devs should run theme update script much more often too - will do in next commit!
