Fix error when attribute value not found
Fix error when attribute value not found

The `getAttributeTypeObject()` method relies on the instance variable `atID` which might not have been set up if the attribute value doesn't exist.

Former-commit-id: 13b396b33a0544a87de0b373677fef1f2c7799fc
Former-commit-id: 4141a60f67e6b21ef6738d2f1c0832a69c55ef58
hissy/concrete5,biplobice/concrete5,deek87/concrete5,hissy/concrete5,mlocati/concrete5,biplobice/concrete5,biplobice/concrete5,olsgreen/concrete5,acliss19xx/concrete5,deek87/concrete5,deek87/concrete5,mlocati/concrete5,rikzuiderlicht/concrete5,olsgreen/concrete5,rikzuiderlicht/concrete5,deek87/concrete5,haeflimi/concrete5,MrKarlDilkington/concrete5,triplei/concrete5-8,mlocati/concrete5,acliss19xx/concrete5,hissy/concrete5,haeflimi/concrete5,MrKarlDilkington/concrete5,concrete5/concrete5,olsgreen/concrete5,rikzuiderlicht/concrete5,jaromirdalecky/concrete5,concrete5/concrete5,KorvinSzanto/concrete5,concrete5/concrete5,haeflimi/concrete5,mlocati/concrete5,triplei/concrete5-8,concrete5/concrete5,a3020/concrete5,jaromirdalecky/concrete5,triplei/concrete5-8,mainio/concrete5,mainio/concrete5,haeflimi/concrete5,hissy/concrete5,jaromirdalecky/concrete5,acliss19xx/concrete5,biplobice/concrete5,a3020/concrete5,jaromirdalecky/concrete5,KorvinSzanto/concrete5,mainio/concrete5,MrKarlDilkington/concrete5,KorvinSzanto/concrete5