[gdm/fix-xdmcp] xdmcp-display-factory: Set supported session types for XDMCP displays

[Ray Strode <halfline src gnome org>]

commit 20cb7fd4371d45dd34595eafad823698322c15cd
Author: Ray Strode <rstrode redhat com>
Date:   Tue Sep 14 11:00:33 2021 -0400

    xdmcp-display-factory: Set supported session types for XDMCP displays
    
    The lower levels of GDM now expect the session types supported by a
    display to be specified up front.
    
    This commit makes sure XDMCP displays do that.

 daemon/gdm-xdmcp-display-factory.c | 6 ++++++
 1 file changed, 6 insertions(+)
---
diff --git a/daemon/gdm-xdmcp-display-factory.c b/daemon/gdm-xdmcp-display-factory.c
index ce8f026e1..abb58faeb 100644
--- a/daemon/gdm-xdmcp-display-factory.c
+++ b/daemon/gdm-xdmcp-display-factory.c
@@ -2131,6 +2131,7 @@ gdm_xdmcp_display_create (GdmXdmcpDisplayFactory *factory,
         GdmDisplay      *display;
         GdmDisplayStore *store;
         gboolean         use_chooser;
+        const char      *session_types[] = { "x11", NULL };
 
         g_debug ("GdmXdmcpDisplayFactory: Creating xdmcp display for %s:%d",
                 hostname ? hostname : "(null)", displaynum);
@@ -2165,6 +2166,11 @@ gdm_xdmcp_display_create (GdmXdmcpDisplayFactory *factory,
                 goto out;
         }
 
+        g_object_set (G_OBJECT (display),
+                      "session-type", session_types[0],
+                      "supported-session-types", session_types,
+                      NULL);
+
         if (! gdm_display_prepare (display)) {
                 gdm_display_unmanage (display);
                 g_object_unref (display);