[gtk+/gtk-3-20] gtkmenusectionbox: remove submenus when the parent item is removed

[Matthias Clasen <matthiasc src gnome org>]

commit 761f19e7d7b81dac63643628b8a1f7935d9f0342
Author: Jonathan Matthew <jonathan d14n org>
Date:   Wed Mar 9 22:44:45 2016 +1000

    gtkmenusectionbox: remove submenus when the parent item is removed
    
    https://bugzilla.gnome.org/show_bug.cgi?id=749405

 gtk/gtkmenusectionbox.c |   16 ++++++++++++++++
 1 files changed, 16 insertions(+), 0 deletions(-)
---
diff --git a/gtk/gtkmenusectionbox.c b/gtk/gtkmenusectionbox.c
index 2de27da..455637d 100644
--- a/gtk/gtkmenusectionbox.c
+++ b/gtk/gtkmenusectionbox.c
@@ -195,9 +195,25 @@ gtk_menu_section_box_remove_func (gint     position,
                                   gpointer user_data)
 {
   GtkMenuSectionBox *box = user_data;
+  GtkMenuTrackerItem *item;
+  GtkWidget *widget;
   GList *children;
 
   children = gtk_container_get_children (GTK_CONTAINER (box->item_box));
+
+  widget = g_list_nth_data (children, position);
+
+  item = g_object_get_data (G_OBJECT (widget), "GtkMenuTrackerItem");
+  if (gtk_menu_tracker_item_get_has_link (item, G_MENU_LINK_SUBMENU)) {
+    GtkWidget *stack, *subbox;
+
+    stack = gtk_widget_get_ancestor (GTK_WIDGET (box->toplevel), GTK_TYPE_STACK);
+    subbox = gtk_stack_get_child_by_name (GTK_STACK (stack), gtk_menu_tracker_item_get_label (item));
+    if (subbox != NULL) {
+      gtk_container_remove (GTK_CONTAINER (stack), subbox);
+    }
+  }
+
   gtk_widget_destroy (g_list_nth_data (children, position));
   g_list_free (children);