Fix check for nil as super class
Fix check for nil as super class

Signed-off-by: Stefan Marr <46f1a0bd5592a2f9244ca321b129902a06b53e03@stefan-marr.de>

smarr/JsSOM,SOM-st/JsSOM,smarr/JsSOM,SOM-st/JsSOM,smarr/JsSOM,smarr/JsSOM,SOM-st/JsSOM,SOM-st/JsSOM