New API for visibility in both CanvasItem and Spatial

visible (property) - access set_visible(bool) is_visible()
is_visible_in_tree() - true when visible and parents visible
show() hide() - for convenience

tools/editor/editor_sub_scene.cpp

@@ -75,7 +75,7 @@ void EditorSubScene::_notification(int p_what) {
 
 	if (p_what==NOTIFICATION_VISIBILITY_CHANGED) {
 
-		if (!is_visible()) {
+		if (!is_visible_in_tree()) {
 
 
 		}