code: function getBaseSelector(elm) {
  	if (typeof isXHTML === 'undefined') {
  		isXHTML = axe.utils.isXHTML(document);
  	}
  	return escapeSelector(isXHTML ? elm.localName : elm.nodeName.toLowerCase());
  }
docs: Return the base CSS selector for a given element
  @param	{HTMLElement} elm				 The element to get the selector for
  @return {String|Array<String>}	Base CSS selector for the node