Replace createTextNode with new Text().

sky/benchmarks/layout/simple-blocks.sky

 <sky>
 <import src="../resources/runner.sky" as="PerfRunner" />
 <style>
 div {
   height: 10px;
 }
 span {
   display: inline;
 }
 </style>
 <div id='content'></div>
 <script>
 var content = document.getElementById('content');
 
 var out = [];
 for (var i = 0; i < 1000; i++) {
   var div = document.createElement('div');
-  div.appendChild(document.createElement('span')).appendChild(document.createTextNode('foo'));
-  div.appendChild(document.createTextNode(' '));
-  div.appendChild(document.createElement('span')).appendChild(document.createTextNode('bar'));
+  div.appendChild(document.createElement('span')).appendChild(new Text('foo'));
+  div.appendChild(new Text(' '));
+  div.appendChild(document.createElement('span')).appendChild(new Text('bar'));
   content.appendChild(div);
 }
 
 var b = document.querySelector('sky');
 
 var runner = new PerfRunner({
   setup: function() {
     b.style.width = '210px';
     getComputedStyle(b).color;
     b.offsetHeight;
 
     b.style.width = '200px';
     getComputedStyle(b).color;
   },
   iterations: 10,
   unit: 'ms',
 });
 
 runner.runAsync(function(done) {
   b.offsetHeight;
   done();
 });
 </script>
 </sky>