function hasNonRootReactChild(container) {
	  var rootEl = getReactRootElementInContainer(container);
	  if (rootEl) {
	    var inst = ReactDOMComponentTree.getInstanceFromNode(rootEl);
	    return !!(inst && inst._hostParent);
	  }
	}
True if the supplied DOM node has a direct React-rendered child that is
not a React root element. Useful for warning in `render`,
`unmountComponentAtNode`, etc.

@param {?DOMElement} node The candidate DOM node.
@return {boolean} True if the DOM element contains a direct child that was
rendered by React but is not a root element.
@internal