diff -r 000000000000 -r 6474c204b198 dom/workers/test/multi_sharedWorker_sharedWorker.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/dom/workers/test/multi_sharedWorker_sharedWorker.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,72 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+"use strict";
+
+if (self.name != "FrameWorker") {
+  throw new Error("Bad worker name: " + self.name);
+}
+
+var registeredPorts = [];
+var errorCount = 0;
+var storedData;
+
+self.onconnect = function(event) {
+  var port = event.ports[0];
+
+  if (registeredPorts.length) {
+    var data = {
+      type: "connect"
+    };
+
+    registeredPorts.forEach(function(registeredPort) {
+      registeredPort.postMessage(data);
+    });
+  }
+
+  port.onmessage = function(event) {
+    switch (event.data.command) {
+      case "start":
+        break;
+
+      case "error":
+        throw new Error("Expected");
+
+      case "store":
+        storedData = event.data.data;
+        break;
+
+      case "retrieve":
+        var data = {
+          type: "result",
+          data: storedData
+        };
+        port.postMessage(data);
+        break;
+
+      default:
+        throw new Error("Unknown command '" + error.data.command + "'");
+    }
+  };
+
+  registeredPorts.push(port);
+};
+
+self.onerror = function(message, filename, lineno) {
+  if (!errorCount++) {
+    var data = {
+      type: "worker-error",
+      message: message,
+      filename: filename,
+      lineno: lineno
+    };
+
+    registeredPorts.forEach(function (registeredPort) {
+      registeredPort.postMessage(data);
+    });
+
+    // Prevent the error from propagating the first time only.
+    return true;
+  }
+};