Fix assignment to array fields using array_length_type
Fix assignment to array fields using array_length_type

Fixes bug 614919.

flobrosch/vala-fixes,rvu95/vala,Distrotech/vala,themiwi/vala,jessevdk/vala,frida/vala,rvu95/vala,flobrosch/vala-fixes,severinh/vala,spidermonkdust/vala,xdave/pvala,themiwi/vala,frida/vala,spidermonkdust/vala,jessevdk/vala,frida/vala,Distrotech/vala,playya/vala,kamanashisroy/aroop,Distrotech/vala,themiwi/vala,GNOME/vala,playya/vala,playya/vala,tjol/vala-tjol,GNOME/vala,tjol/vala-tjol,severinh/vala,GNOME/vala,frida/vala,severinh/vala,kamanashisroy/aroop,tjol/vala-tjol,rvu95/vala,frida/vala,spidermonkdust/vala,GNOME/vala,jessevdk/vala,kamanashisroy/aroop,flobrosch/vala-fixes