67254ea37c
The callback would just assume that it's only called on materials, which may in fact not be the case. It could also be called for other ID types and layer collections (see `outliner_do_libdata_operation()`). Properly check this now. Also avoid faling silently when the object or object-data to unlink from couldn't be determined. Report this to the user. Operators that just do nothing are confusing.