* rational.c (float_to_r): always returns rational.
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_1_9_1@27982 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
merges r23892 from trunk into ruby_1_9_1.¶
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_1_9_1@27982 b2dd03c8-39d4-4d8f-98ff-823fe69b080e