src/js/mixins/PortalMixins.js
function(children, element) {
        this.portalNode = document.createElement('div');
        (element || document.body).appendChild(this.portalNode);
        ReactDOM.render(children, this.portalNode);
    }
function(children, element) {
        this.portalNode = document.createElement('div');
        (element || document.body).appendChild(this.portalNode);
        ReactDOM.render(children, this.portalNode);
    }
Creates a new detatched DOM node to render child components within.
@param {Object} children  The items to be displayed in the portal.
@param {Object} [element] Optional HTML Element to append PageMessage object to.