dynamic include(
elem,
PolymerDom parent
)

Not documented.

Source

include(elem, PolymerDom parent) {
  removeChildren(parent);

  if (parent != null) {
    if (elem is HtmlElement) {
      parent.append(elem);
    } else if (elem is String) {
      HtmlElement _elem = document.createElement(elem);
      parent.append(_elem);
    }
    PolymerDom.flush();
  }
}