removeByDOMNode method
Removes domNode from parent. Also performs on mapped element.
Implementation
DOMNodeMapping<T>? removeByDOMNode(DOMNode? domNode) {
  if (domNode == null || !domNode.hasParent) return null;
  var nodeRuntime = domNode.runtime;
  nodeRuntime.remove();
  domNode.remove();
  unmap(domNode, nodeRuntime.node);
  return DOMNodeMapping(this, domNode, nodeRuntime.node);
}