* lib/tmpdir.rb (Dir.mktmpdir): check if the permission of the
  parent directory only when using the default temporary
  directory, and no check against user given directory.  the
  security is the user's responsibility in that case.
  [ruby-core:91216] [Bug #15555]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@66909 b2dd03c8-39d4-4d8f-98ff-823fe69b080e