/// <summary>
///
/// </summary>
/// <param name="node"></param>
/// <param name="child"></param>
/// <returns></returns>
private Node PreInsert(Node node, Node child)
{
// Reference: https://www.w3.org/TR/2015/REC-dom-20151119/#concept-node-pre-insert
EnsurePreInsertionValidity(node, child);
if (node == child)
{
child = node.NextSibling;
}
OwnerDocument.AdoptNode(node);
Insert(node, child);
return(node);
}