diff -r 000000000000 -r 6474c204b198 dom/workers/test/clearTimeouts_worker.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/dom/workers/test/clearTimeouts_worker.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,12 @@
+var count = 0;
+function timerFunction() {
+  if (++count == 30) {
+    close();
+    postMessage("ready");
+    while (true) { }
+  }
+}
+
+for (var i = 0; i < 10; i++) {
+  setInterval(timerFunction, 500);
+}