From 96f8f450de1201e1d0399b7e66582e4c8942f03d Mon Sep 17 00:00:00 2001
From: Brian Birtles <birtles@gmail.com>
Date: Wed, 17 Feb 2016 13:38:31 +0900
Subject: [PATCH] Bug 1244414 - Create iframe element from script to avoid
 racing with the load event; r=bz

---
 .../tests/web-animations/animatable/animate.html      | 11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)
diff --git a/testing/web-platform/tests/web-animations/animatable/animate.html b/testing/web-platform/tests/web-animations/animatable/animate.html
index d649aef28af7..aff546c87659 100644
--- a/testing/web-platform/tests/web-animations/animatable/animate.html
+++ b/testing/web-platform/tests/web-animations/animatable/animate.html
@@ -9,8 +9,6 @@
 <link rel="stylesheet" href="/resources/testharness.css">
 <body>
 <div id="log"></div>
-<iframe src="data:text/html;charset=utf-8," width="10" height="10"
-  id="iframe"></iframe>
 <script>
 'use strict';
 
@@ -104,13 +102,20 @@ test(function(t) {
 }, 'Element.animate() correctly sets the Animation\'s timeline');
 
 async_test(function(t) {
-  var iframe = document.getElementById('iframe');
+  var iframe = document.createElement('iframe');
+  iframe.src = 'data:text/html;charset=utf-8,';
+  iframe.width = 10;
+  iframe.height = 10;
+
   iframe.addEventListener('load', t.step_func(function() {
     var div = createDiv(t, iframe.contentDocument);
     var anim = div.animate({ opacity: [ 0, 1 ] }, 2000);
     assert_equals(anim.timeline, iframe.contentDocument.timeline);
+    iframe.remove();
     t.done();
   }));
+
+  document.body.appendChild(iframe);
 }, 'Element.animate() correctly sets the Animation\'s timeline when ' +
    'triggered on an element in a different document');
 
