Get rid of a warning on Rails master.
Get rid of a warning on Rails master.

concord-consortium/haml,keithpitty/haml,nazar-pc/haml,dg1dd1ngs/haml,sideci-sample/sideci-sample-haml,nazar-pc/haml,uniba/hamldoc_ja,haml/haml,haml/haml,keithpitty/haml,stanhu/haml,haml/haml,haml/haml,tangposmarvin/haml,macressler/haml,tangposmarvin/haml,stanhu/haml,macressler/haml,dg1dd1ngs/haml,amatsuda/haml