[gnome-builder] editor: handle initialization gracefully

[Christian Hergert <chergert src gnome org>]

commit b74dc99742f6597077ea612d9cb12a279f67fe92
Author: Christian Hergert <chergert redhat com>
Date:   Fri Jan 5 20:31:19 2018 -0800

    editor: handle initialization gracefully

 src/libide/editor/ide-editor-utilities.c |    7 ++++---
 1 files changed, 4 insertions(+), 3 deletions(-)
---
diff --git a/src/libide/editor/ide-editor-utilities.c b/src/libide/editor/ide-editor-utilities.c
index b2fa67d..e3837e6 100644
--- a/src/libide/editor/ide-editor-utilities.c
+++ b/src/libide/editor/ide-editor-utilities.c
@@ -81,9 +81,10 @@ ide_editor_utilities_add (GtkContainer *container,
                                NULL);
     }
 
-  gtk_container_foreach (GTK_CONTAINER (self->stack_switcher),
-                         tweak_radio_button,
-                         NULL);
+  if (self->stack_switcher != NULL)
+    gtk_container_foreach (GTK_CONTAINER (self->stack_switcher),
+                           tweak_radio_button,
+                           NULL);
 }
 
 static void