Ruby

• array.c (ary_partial0): recovers mistakenly feature change at r19723.
  Array#[m,n] had returned an Array even for an instance of a
  subclass.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_1_9_1@20076 b2dd03c8-39d4-4d8f-98ff-823fe69b080e