probably not much performance benefit, but it sure is good at
identifying leftover intermediate variables from previous
refactorings.

Change-Id: I3ce16fe496ac2733c1cb0a35f74c0fc9193cc657
Reviewed-on: https://gerrit.libreoffice.org/24026Reviewed-by: Noel Grandin <noelgrandin@gmail.com>
Tested-by: Noel Grandin <noelgrandin@gmail.com>