[gdm] xdmcp-display-factory: fix signal prototype

[Ray Strode <halfline src gnome org>]

commit 2a3d5a7c402534c3611956fed930394a51cb00c5
Author: Ray Strode <rstrode redhat com>
Date:   Fri Mar 31 14:58:26 2017 -0400

    xdmcp-display-factory: fix signal prototype
    
    The callback was getting called with the wrong arguments leading
    to spew in the logs and necessary code not getting run!
    
    https://bugzilla.gnome.org/show_bug.cgi?id=780787

 daemon/gdm-xdmcp-display-factory.c |    3 ++-
 1 files changed, 2 insertions(+), 1 deletions(-)
---
diff --git a/daemon/gdm-xdmcp-display-factory.c b/daemon/gdm-xdmcp-display-factory.c
index b9ab921..c5f7ddb 100644
--- a/daemon/gdm-xdmcp-display-factory.c
+++ b/daemon/gdm-xdmcp-display-factory.c
@@ -2050,7 +2050,8 @@ on_hostname_selected (GdmXdmcpChooserDisplay *display,
 }
 
 static void
-on_client_disconnected (GdmDisplay *display)
+on_client_disconnected (GdmSession *session,
+                        GdmDisplay *display)
 {
         if (gdm_display_get_status (display) != GDM_DISPLAY_MANAGED)
                 return;