function getMarkupWrap(nodeName) {
	  !!!dummyNode ? process.env.NODE_ENV !== 'production' ? invariant(false, 'Markup wrapping node not initialized') : invariant(false) : void 0;
	  if (!markupWrap.hasOwnProperty(nodeName)) {
	    nodeName = '*';
	  }
	  if (!shouldWrap.hasOwnProperty(nodeName)) {
	    if (nodeName === '*') {
	      dummyNode.innerHTML = '<link />';
	    } else {
	      dummyNode.innerHTML = '<' + nodeName + '></' + nodeName + '>';
	    }
	    shouldWrap[nodeName] = !dummyNode.firstChild;
	  }
	  return shouldWrap[nodeName] ? markupWrap[nodeName] : null;
	}
Gets the markup wrap configuration for the supplied `nodeName`.

NOTE: This lazily detects which wraps are necessary for the current browser.

@param {string} nodeName Lowercase `nodeName`.
@return {?array} Markup wrap configuration, if applicable.