Generate correct unref expressions for subtypes of special cases
Generate correct unref expressions for subtypes of special cases

Fixes bug 617377.

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