[glade] Fixed crasher on exit removing project hierarchy from GladeDesignLayout

[Juan Pablo Ugarte <jpu src gnome org>]

commit c5dc2ea021c44b9b98935667c865077079e8fb84
Author: Juan Pablo Ugarte <juanpablougarte gmail com>
Date:   Thu Mar 28 16:52:05 2013 -0300

    Fixed crasher on exit removing project hierarchy from GladeDesignLayout

 gladeui/glade-design-layout.c |   16 ++++++++++++++++
 1 files changed, 16 insertions(+), 0 deletions(-)
---
diff --git a/gladeui/glade-design-layout.c b/gladeui/glade-design-layout.c
index 0e90e43..98418f1 100644
--- a/gladeui/glade-design-layout.c
+++ b/gladeui/glade-design-layout.c
@@ -1868,6 +1868,21 @@ glade_design_layout_constructor (GType                  type,
 }
 
 static void
+glade_design_layout_dispose (GObject *object)
+{
+  GtkWidget *child;
+
+  /* NOTE: Remove child from hierarchy!
+   * This way we ensure gtk_widget_destroy() will not be called on it.
+   * Glade API like glade_widget_get_children() depends on children hierarchy. 
+   */
+  if ((child = gtk_bin_get_child (GTK_BIN (object))))
+    gtk_container_remove (GTK_CONTAINER (object), child);
+
+  G_OBJECT_CLASS (glade_design_layout_parent_class)->dispose (object);
+}
+
+static void
 glade_design_layout_finalize (GObject *object)
 {
   GladeDesignLayout *layout = GLADE_DESIGN_LAYOUT (object);
@@ -1977,6 +1992,7 @@ glade_design_layout_class_init (GladeDesignLayoutClass * klass)
   container_class = GTK_CONTAINER_CLASS (klass);
 
   object_class->constructor = glade_design_layout_constructor;
+  object_class->dispose = glade_design_layout_dispose;
   object_class->finalize = glade_design_layout_finalize;
   object_class->set_property = glade_design_layout_set_property;
   object_class->get_property = glade_design_layout_get_property;