code: func (c *DOM) CollectClassNamesFromSubtree(nodeId int) ([]string, error) {
  	var v DOMCollectClassNamesFromSubtreeParams
  	v.NodeId = nodeId
  	return c.CollectClassNamesFromSubtreeWithParams(&v)
  }
docs: // CollectClassNamesFromSubtree - Collects class names for the node with given id and all of it's child nodes.
  // nodeId - Id of the node to collect class names.
  // Returns -  classNames - Class name list.