fix a typo [ci skip]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@45358 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
* 2014-03-18

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@45359 b2dd03c8-39d4-4d8f-98ff-823fe69b080e