LayoutTests/resize-observer/resources/iframe1.html - WebKit - Git at Google

 <!DOCTYPE html>
 <div id="iframe1-target1" style="width:100px;height:100px;">iframe1-t1</div>

 <script type="text/javascript">
 'use strict';
 window.parent.postMessage('readyToTest', '*');
 </script>
	<!DOCTYPE html>
	<div id="iframe1-target1" style="width:100px;height:100px;">iframe1-t1</div>

	<script type="text/javascript">
	'use strict';
	window.parent.postMessage('readyToTest', '*');
	</script>