Handle drawing of relationship lines better to take in to account invisible children

scene/gui/tree.cpp

@@ -2169,7 +2169,7 @@ int Tree::draw_item(const Point2i &p_pos, const Point2 &p_draw_ofs, const Size2
 				int parent_ofs = p_pos.x + cache.item_margin;
 				Point2i root_pos = Point2i(root_ofs, children_pos.y + label_h / 2) - cache.offset + p_draw_ofs;
 
-				if (c->get_first_child() != nullptr) {
+				if (c->get_visible_child_count() > 0) {
 					root_pos -= Point2i(cache.arrow->get_width(), 0);
 				}