* win32/file.c (rb_file_expand_path_internal): do not make invalid
(or ADS) path if the path has a drive letter, the result also
should have be under it. [ruby-core:68130] [Bug #10858]
* win32/file.c (rb_file_expand_path_internal): neither the drive
of base directory nor the current drive are involved in the
result if different than the drive of path.
[ruby-core:68130] [Bug #10858]
merge revision(s) 49618,49640: [Backport #10858]
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_2_2@49671 b2dd03c8-39d4-4d8f-98ff-823fe69b080e