diff -r 000000000000 -r 6474c204b198 dom/workers/test/file_url.jsm
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/dom/workers/test/file_url.jsm	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,23 @@
+this.EXPORTED_SYMBOLS = ['checkFromJSM'];
+
+this.checkFromJSM = function checkFromJSM(ok, is, finish) {
+  let worker = new ChromeWorker("jsm_url_worker.js");
+  worker.onmessage = function(event) {
+
+   if (event.data.type == 'finish') {
+     finish();
+    } else if (event.data.type == 'status') {
+      ok(event.data.status, event.data.msg);
+    }
+  }
+
+  var self = this;
+  worker.onerror = function(event) {
+    is(event.target, worker);
+    ok(false, "Worker had an error: " + event.data);
+    self.worker.terminate();
+    finish();
+  };
+
+  worker.postMessage(0);
+}