[mutter/wayland] xwayland: Detect a fail to fork

[Jasper St. Pierre <jstpierre src gnome org>]

commit c4c0b5f0ab461a6346ad0820b41cf9eea25f9e33
Author: Jasper St. Pierre <jstpierre mecheye net>
Date:   Wed Apr 2 13:03:17 2014 -0400

    xwayland: Detect a fail to fork

 src/wayland/meta-xwayland.c |    4 ++++
 1 files changed, 4 insertions(+), 0 deletions(-)
---
diff --git a/src/wayland/meta-xwayland.c b/src/wayland/meta-xwayland.c
index 72be352..2904965 100644
--- a/src/wayland/meta-xwayland.c
+++ b/src/wayland/meta-xwayland.c
@@ -402,6 +402,10 @@ meta_xwayland_start (MetaXWaylandManager *manager,
           exit (EXIT_FAILURE);
         }
     }
+  else if (manager->pid == -1)
+    {
+      g_error ("Failed to fork: %m");
+    }
 
   g_child_watch_add (manager->pid, xserver_died, NULL);
   manager->client = wl_client_create (wl_display, sp[0]);