normalizeTextNode(node) {
    if (!node) {
      return;
    }
    if (node.nodeType === 3) {
      while (node.nextSibling && node.nextSibling.nodeType === 3) {
        node.nodeValue += node.nextSibling.nodeValue;
        node.parentNode.removeChild(node.nextSibling);
      }
    } else {
      this.normalizeTextNode(node.firstChild);
    }
    this.normalizeTextNode(node.nextSibling);
  }
Normalizes text nodes. It's a workaround for the native normalize method
that has a bug in IE (see attached link). Should only be used in IE
browsers as it's slower than the native method.
@see {@link http://tinyurl.com/z5asa8c}
@param {HTMLElement} node - The DOM node to normalize
@access protected