Ruby

• win32/{dir.h, win32.c} (rb_w32_readdir_with_enc): new function to
  read entry with specified enc.

   * win32/win32.c (readdir_internal): extract from rb_w32_opendir(). * win32/win32.c (opendir_internal): extract from rb_w32_readdir(). * dir.c (dir_read, dir_each): use new READDIR macro instead of readdir() to pass enc for special version of readdir, such as above. 

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@22087 b2dd03c8-39d4-4d8f-98ff-823fe69b080e