diff -r 000000000000 -r 6474c204b198 dom/events/test/error_event_worker.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/dom/events/test/error_event_worker.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,15 @@
+ addEventListener("error", function(e) {
+     var obj = {};
+     for (var prop of ["message", "filename", "lineno"]) {
+       obj[prop] = e[prop]
+     }
+     obj.type = "event";
+     postMessage(obj);
+});
+onerror = function(message, filename, lineno) {
+  var obj = { message: message, filename: filename, lineno: lineno,
+	      type: "callback" }
+  postMessage(obj);
+  return false;
+}
+throw new Error("workerhello");