Determine Seat can_tty value without login1

Author: Gliese852

src/lightdm.c

@@ -26,6 +26,7 @@
 #include "display-manager-service.h"
 #include "xdmcp-server.h"
 #include "vnc-server.h"
+#include "vt.h"
 #include "seat-xdmcp-session.h"
 #include "seat-xvnc.h"
 #include "x-server.h"
@@ -918,6 +919,10 @@ main (int argc, char **argv)
             {
                 set_seat_properties (seat, NULL);
                 seat_set_property (seat, "exit-on-failure", "true");
+
+                /* in the absence of login1 we find out this using our own heuristics */
+                seat_set_can_tty (seat, vt_can_multi_seat ());
+
                 if (!display_manager_add_seat (display_manager, seat))
                     return EXIT_FAILURE;
             }