StoredMaterialManager: make addMaterial and getElement non-const
Follow-up MR to !54069 (merged) that makes the remaining StoredMaterialManager interfaces const-correct, i.e.:
- make
addMaterialandgetElementnon-const - remove mutables
- various
const(cast) fixes - enable thread-checker for
GeoModelSvc
This was discussed with @tsulaia and @ssnyder on !54024 (closed).
Edited by Frank Winklmeier