Move scale factors inside the properties container

Change-Id: Ic2417796d1e1cf150124ede660b53d3a01d70aab
Reviewed-on: https://gerrit.libreoffice.org/12480
Reviewed-by: Caolán McNamara <caolanm@redhat.com>
Tested-by: Caolán McNamara <caolanm@redhat.com>