[gtk] node editor: Manually unrealize all created renderers

[Timm Bäder <baedert src gnome org>]

commit 0f3ca349e7a013955cc0d4965207b13763c0b342
Author: Timm Bäder <mail baedert org>
Date:   Sat Jul 13 09:37:47 2019 +0200

    node editor: Manually unrealize all created renderers
    
    This has not been a problem before since we were leaking them.

 demos/node-editor/node-editor-window.c | 8 ++++++++
 1 file changed, 8 insertions(+)
---
diff --git a/demos/node-editor/node-editor-window.c b/demos/node-editor/node-editor-window.c
index 08559f167c..9e880354f3 100644
--- a/demos/node-editor/node-editor-window.c
+++ b/demos/node-editor/node-editor-window.c
@@ -707,6 +707,14 @@ static void
 node_editor_window_unrealize (GtkWidget *widget)
 {
   NodeEditorWindow *self = NODE_EDITOR_WINDOW (widget);
+  guint i;
+
+  for (i = 0; i < g_list_model_get_n_items (G_LIST_MODEL (self->renderers)); i ++)
+    {
+      gpointer item = g_list_model_get_item (G_LIST_MODEL (self->renderers), i);
+      gsk_renderer_unrealize (gtk_renderer_paintable_get_renderer (item));
+      g_object_unref (item);
+    }
 
   g_list_store_remove_all (self->renderers);