GObject: Remove unused klass variable from constructors
GObject: Remove unused klass variable from constructors

Distrotech/vala,playya/vala,GNOME/vala,themiwi/vala,flobrosch/vala-fixes,frida/vala,kamanashisroy/aroop,jessevdk/vala,tjol/vala-tjol,Distrotech/vala,spidermonkdust/vala,frida/vala,xdave/pvala,lovebug356/vala,rvu95/vala,playya/vala,rvu95/vala,flobrosch/vala-fixes,Jc2k/vala,severinh/vala,GNOME/vala,phako/vala,GNOME/vala,frida/vala,kamanashisroy/aroop,playya/vala,phako/vala,flobrosch/vala-fixes,frida/vala,kamanashisroy/aroop,severinh/vala,GNOME/vala,rvu95/vala,jessevdk/vala,themiwi/vala,frida/vala,lovebug356/vala,tjol/vala-tjol,Jc2k/vala,tjol/vala-tjol,severinh/vala,spidermonkdust/vala,spidermonkdust/vala,jessevdk/vala,themiwi/vala,Distrotech/vala