V547 Expression 'Oep <= Osp' is always false.

Some of the conditions in the type detection code weren't reachable.
Also moved the code from class member to static function.

Change-Id: Iaf9dbe8ab15a1970b5cd580cf5d868715a234d02
Reviewed-on: https://gerrit.libreoffice.org/63230
Tested-by: Jenkins
Reviewed-by: Mike Kaganski <mike.kaganski@collabora.com>