Fix foldertestsources crashing if the source folder is missing.
Fix foldertestsources crashing if the source folder is missing.

iskiselev/JSIL,hach-que/JSIL,sq/JSIL,sander-git/JSIL,acourtney2015/JSIL,sq/JSIL,acourtney2015/JSIL,iskiselev/JSIL,sander-git/JSIL,Trattpingvin/JSIL,sander-git/JSIL,x335/JSIL,antiufo/JSIL,antiufo/JSIL,TukekeSoft/JSIL,FUSEEProjectTeam/JSIL,dmirmilshteyn/JSIL,FUSEEProjectTeam/JSIL,iskiselev/JSIL,volkd/JSIL,iskiselev/JSIL,x335/JSIL,TukekeSoft/JSIL,mispy/JSIL,hach-que/JSIL,antiufo/JSIL,antiufo/JSIL,acourtney2015/JSIL,dmirmilshteyn/JSIL,dmirmilshteyn/JSIL,acourtney2015/JSIL,FUSEEProjectTeam/JSIL,hach-que/JSIL,volkd/JSIL,Trattpingvin/JSIL,volkd/JSIL,sq/JSIL,mispy/JSIL,dmirmilshteyn/JSIL,acourtney2015/JSIL,FUSEEProjectTeam/JSIL,hach-que/JSIL,volkd/JSIL,x335/JSIL,sq/JSIL,Trattpingvin/JSIL,x335/JSIL,sander-git/JSIL,mispy/JSIL,sq/JSIL,iskiselev/JSIL,sander-git/JSIL,TukekeSoft/JSIL,volkd/JSIL,FUSEEProjectTeam/JSIL,Trattpingvin/JSIL,mispy/JSIL,TukekeSoft/JSIL,hach-que/JSIL