fix select: null pointer for non-multiple
fix select: null pointer for non-multiple

The default value for the internal list was "undefined" instead of "[]".
It caused a null pointer when trying to convert the model to the
internal list. Fixed by giving the right default value.

daniel-oliveiravas/lumX,jefvel/lumX,clementprevot/lumX,daniel-oliveiravas/lumX,b-cuts/lumX,jason588/lumX,b-cuts/lumX,Ener-Getick/lumX,noikiy/lumX,ezzye/write-to-be-heard,terradatum/lumX,hinablue/lumX,bright-sparks/lumX,jayaguilar/lumX,terradatum/lumX,itxd/lumX,b-cuts/lumX,jason588/lumX,jason588/lumX,cupceavictor/lumX,noikiy/lumX,clementprevot/lumX,jayaguilar/lumX,daniel-oliveiravas/lumX,bright-sparks/lumX,jefvel/lumX,hinablue/lumX,bijeeshtk/lumx,bijeeshtk/lumx,clementprevot/lumX,daniel-oliveiravas/lumX,noikiy/lumX,jefvel/lumX,jason588/lumX,itxd/lumX,bright-sparks/lumX,bright-sparks/lumX,lumapps/lumX,Ener-Getick/lumX,Ener-Getick/lumX,jayaguilar/lumX,noikiy/lumX,lumapps/lumX,cupceavictor/lumX,ezzye/write-to-be-heard,cupceavictor/lumX,bijeeshtk/lumx,itxd/lumX,bijeeshtk/lumx,cupceavictor/lumX,hinablue/lumX,Ener-Getick/lumX,b-cuts/lumX,terradatum/lumX,ezzye/write-to-be-heard,terradatum/lumX,jefvel/lumX,jayaguilar/lumX,clementprevot/lumX,lumapps/lumX,lumapps/lumX,itxd/lumX,hinablue/lumX,ezzye/write-to-be-heard