[1.7.x] Fixed #22681 -- Made TarArchive recognize leading directories properly.

        # note: python<=2.5 doesn't seem to know about pax headers, filter them

        members = [member for member in self._archive.getmembers()

                   if member.name != 'pax_global_header']

        leading = self.has_leading_dir(members)

        leading = self.has_leading_dir(x.name for x in members)

        for member in members:

            name = member.name

            if leading: