createTreeWalker method
Implementation
TreeWalker createTreeWalker(Node root,
        [int? whatToShow = 0xFFFFFFFF, NodeFilter? filter]) =>
    js_util.callMethod(this, 'createTreeWalker', [root, whatToShow, filter]);TreeWalker createTreeWalker(Node root,
        [int? whatToShow = 0xFFFFFFFF, NodeFilter? filter]) =>
    js_util.callMethod(this, 'createTreeWalker', [root, whatToShow, filter]);