downloader.rb: compatibility with old BASERUBY

* tool/downloader.rb (Downloader.download): get rid of post
  arguments for compatibility with old BASERUBY.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@47729 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
ruby.h: warn untyped Data

* include/ruby/ruby.h (rb_data_object_alloc_warning): warn
  Data_Wrap_Struct and Data_Make_Struct only if
  RUBY_UNTYPED_DATA_WARNING is set to 1.

* include/ruby/ruby.h (rb_data_object_get_warning): ditto for
  Data_Get_Struct.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@47730 b2dd03c8-39d4-4d8f-98ff-823fe69b080e