[gtk+] GtkApplication: avoid a crash

[Matthias Clasen <matthiasc src gnome org>]

commit c0ac3c3386b555832ad0dc34745ad26dcd184fb4
Author: Matthias Clasen <mclasen redhat com>
Date:   Wed Apr 8 15:44:21 2015 -0400

    GtkApplication: avoid a crash
    
    It can apparently happen that we get focus in events
    on windows after gtk_application_shutdown() has been
    called. Avoid an unnecessary crash in this case.
    
    See
    https://bugzilla.redhat.com/show_bug.cgi?id=1176339

 gtk/gtkapplication.c |    4 +++-
 1 files changed, 3 insertions(+), 1 deletions(-)
---
diff --git a/gtk/gtkapplication.c b/gtk/gtkapplication.c
index 80658c5..91ef355 100644
--- a/gtk/gtkapplication.c
+++ b/gtk/gtkapplication.c
@@ -506,7 +506,9 @@ gtk_application_focus_in_event_cb (GtkWindow      *window,
       priv->windows = g_list_concat (link, priv->windows);
     }
 
-  gtk_application_impl_active_window_changed (application->priv->impl, window);
+  if (application->priv->impl)
+    gtk_application_impl_active_window_changed (application->priv->impl, window);
+
   g_object_notify (G_OBJECT (application), "active-window");
 
   return FALSE;