;       var e = d.nextSibling;        var records = observer.takeRecords();       assert.equal(records.length, 0);       expectMutationRecord(records[0], {         type: 'childList',         target: a,         addedNodes: [d, e],         previousSibling: null,         nextSibling: b       });     });      test('insertAdjacentHTML beforeend', function() {       var a = document.createElement('a');       a.innerHTML = '<b></b><c></c>';       var b = a.firstChild;       var c = a.lastChild;        var observer = new MutationObserver(function() {});       observer.observe(a, {         childList: true       });        a.insertAdjacentHTML('