[gnome-builder/wip/gtk4-port] plugins/symbol-tree: fix extraneous tree expanders

[Christian Hergert <chergert src gnome org>]

commit ba10ba2a7dd0b35a748918785c8faccb51291408
Author: Christian Hergert <chergert redhat com>
Date:   Fri Apr 22 18:03:01 2022 -0700

    plugins/symbol-tree: fix extraneous tree expanders

 src/plugins/symbol-tree/gbp-symbol-popover.c | 3 +++
 1 file changed, 3 insertions(+)
---
diff --git a/src/plugins/symbol-tree/gbp-symbol-popover.c b/src/plugins/symbol-tree/gbp-symbol-popover.c
index 37d4ae753..8542eb18a 100644
--- a/src/plugins/symbol-tree/gbp-symbol-popover.c
+++ b/src/plugins/symbol-tree/gbp-symbol-popover.c
@@ -236,6 +236,9 @@ get_child_model (gpointer item,
   g_assert (IDE_IS_SYMBOL_NODE (node));
   g_assert (IDE_IS_SYMBOL_TREE (tree));
 
+  if (ide_symbol_tree_get_n_children (tree, node) == 0)
+    return NULL;
+
   return G_LIST_MODEL (gbp_symbol_list_model_new (tree, node));
 }