glib-2.0: Make GLib.Log.default_handler a GLib.LogFunc
glib-2.0: Make GLib.Log.default_handler a GLib.LogFunc

Fixes bug 638682.

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