Correctly return an AcceptsListFor default of `false`.
Correctly return an AcceptsListFor default of `false`.

A falsey default would previously fall through to the empty list, which AcceptsValueFor would shift, returning nil. This correctly returns `[false]`, which produces the correct default in AcceptsValueFor.

victorklos/babushka,victorklos/babushka,victorklos/babushka