Make skip-cleaning-up-anonymous-wrappers-when-subtree-being-destroyed.html deterministic

third_party/WebKit/LayoutTests/fast/block/skip-cleaning-up-anonymous-wrappers-when-subtree-being-destroyed.html

Index: third_party/WebKit/LayoutTests/fast/block/skip-cleaning-up-anonymous-wrappers-when-subtree-being-destroyed.html
diff --git a/third_party/WebKit/LayoutTests/fast/block/skip-cleaning-up-anonymous-wrappers-when-subtree-being-destroyed.html b/third_party/WebKit/LayoutTests/fast/block/skip-cleaning-up-anonymous-wrappers-when-subtree-being-destroyed.html
index d957e405dea82b343041e180e9c177225e79f7e2..f74914da6a91b4497b0cf8aec1e3a3d8ffc19d72 100644
--- a/third_party/WebKit/LayoutTests/fast/block/skip-cleaning-up-anonymous-wrappers-when-subtree-being-destroyed.html
+++ b/third_party/WebKit/LayoutTests/fast/block/skip-cleaning-up-anonymous-wrappers-when-subtree-being-destroyed.html
@@ -6,7 +6,12 @@
     </table>
 </object>
 <script>
-    window.setInterval(function(){
+    if (window.testRunner) {
+        testRunner.dumpAsText();
+        testRunner.waitUntilDone();
+    }
+    var count = 0;
+    var id = window.setInterval(function(){
             var oe = document.getElementsByTagName("*");
             for (var i = 0; i < oe.length; i++) {
                 var o = oe.item(i);
@@ -15,6 +20,11 @@
                     p.replaceChild(document.createTextNode("PASS"), o)
                 }
             }
+            if (++count === 2) {
+                window.clearInterval(id);
+                if (window.testRunner)
+                    testRunner.notifyDone();
+            }
             });
 </script>
 <p id="title">crbug.com/549544: Don't clean up anonymous wrappers when the element's branch or sub-tree is being destroyed.</p>