On Rails 4 .scoped is deprecated. Calling .all on the model returns the equivalent ActiveRecord relation object on Rails 4, but on Rails 3 it returns an Array right away.
A proper replacement we can use is where(nil) - it's ugly but it returns the same relation in both Rails 3 and 4.
We could possibly substitute these by .all after the Rails 4 migration if they feel too 'unidiomatic'.