bash4, here-documents, <<-EOF ... indented EOF terminator errors out.

This snippet, taken from /etc/bash.bashrc, errors out on the here document, even though the
man page states that <<-EOF should allow for the terminating EOF to be indented.

#!/bin/bash
# sudo hint
if [ ! -e "$HOME/.sudo_as_admin_successful" ] && [ ! -e "$HOME/.hushlogin" ] ; then
  case " $(groups) " in *\ admin\ *)
    if [ -x /usr/bin/sudo ]; then
      cat <<-EOF
        To run a command as administrator (user "root"), use "sudo <command>".
        See "man sudo_root" for details.
      EOF
    fi
  esac
fi

Error message is:
./test.sh: line 13: warning: here-document at line 6 delimited by end-of-file (wanted `EOF')
./test.sh: line 14: syntax error: unexpected end of file