rails/rails — pull request #12870 by sauliusg (2013-11-13 12:01:17+00:00)
Title: Fix syntax error in atom_feed example [ci skip]

Builder's #tag! takes either String or Symbol as the first parameter (see http://builder.rubyforge.org/classes/Builder/XmlBase.html#M000017).

This is also wrong on `4.0-stable` and `3-2-stable`.