rails/rails — pull request #12110 by strzalek (2013-09-02 21:27:54+00:00)
Title: Revert default protected instance vars

It wasn't good idea and after discussing it with @josevalim we've decided that it would be better to revert this back to previous solution with instance variable instead of calling methods. It was more expensive (calling super & array concatenation) without much value added.