ranges too.

* range.c (rb_range_beg_len): length calculation was wrong.

* eval.c (rb_call): should set T_ICLASS in the frame->last_class.
  [ruby-core:01110]


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@3899 b2dd03c8-39d4-4d8f-98ff-823fe69b080e