D-Bus: Fix warning and leak in proxy creation in dbus-glib clients
D-Bus: Fix warning and leak in proxy creation in dbus-glib clients

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