gdbus: don't send unexpected replies
gdbus: don't send unexpected replies

gdbus sets NO_REPLY_EXPECTED when no callback is given to
g_dbus_connection_call(). It makes sense that it also handles the server
side correctly by discarding replies to clients that don't want one.

https://bugzilla.gnome.org/show_bug.cgi?id=755421

endlessm/glib,Distrotech/glib,endlessm/glib,MathieuDuponchelle/glib,MathieuDuponchelle/glib,endlessm/glib,endlessm/glib,mzabaluev/glib,MathieuDuponchelle/glib,johne53/MB3Glib,Distrotech/glib,mzabaluev/glib,mzabaluev/glib,johne53/MB3Glib,Distrotech/glib,Distrotech/glib,johne53/MB3Glib,mzabaluev/glib,johne53/MB3Glib,mzabaluev/glib,johne53/MB3Glib,Distrotech/glib,MathieuDuponchelle/glib,johne53/MB3Glib,MathieuDuponchelle/glib,endlessm/glib