* file.c (rb_enc_path_next, rb_enc_path_skip_prefix)
  (rb_enc_path_last_separator, rb_enc_path_end)
  (ruby_enc_find_basename, ruby_enc_find_extname): encoding-aware
  path handling functions.

* file.c (rb_home_dir, file_expand_path, rb_realpath_internal)
  (rb_file_s_basename, rb_file_dirname, rb_file_s_extname)
  (rb_file_join): should respect the encodings of arguments than
  file system encoding.  [ruby-dev:45145] [Bug #5919]

* dir.c (check_dirname, ruby_glob0): ditto.

* ext/pathname/pathname.c (path_sub_ext): ditto.

* util.c, include/ruby/util.h (ruby_add_suffix): remove the function.
  [Bug #5153] [ruby-core:38736]

* io.c (argf_next_argv): remove the call of above function.

* ext/-test-/add_suffix, test/-ext-/test_add_suffix.rb: remove the test
  extension module because this is only for testsing ruby_add_suffix().

* LEGAL: remove the mention about a part of util.c, because now we
  removed the part.

* io.c (argf_next_argv): now the new filename is not guranteed to
  use, so should check the return value of rename(2).

* test/ruby/test_argf.rb (TestArgf#test_inplace_rename_impossible):
  now we expect same result with other platforms on no_safe_rename
  platforms (=Windows).


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_1_9_3@37330 b2dd03c8-39d4-4d8f-98ff-823fe69b080e