regression from
    commit b4fc9965
    loplugin:useuniqueptr in SdrHdlList

Change-Id: I53e2adee9a1ad8ef73de5a9601238187a6002241
Reviewed-on: https://gerrit.libreoffice.org/62714
Tested-by: Jenkins
Reviewed-by: Noel Grandin <noel.grandin@collabora.co.uk>