Enabled a number of worker tests on various platforms.

chrome/test/data/workers/worker_utils.js

+var shared_worker_count = 0;
+function getWorker(worker_url)
+{
+  // Create either a dedicated or shared worker, depending on flags
+  var url = document.location.toString();
+  if (url.search("shared") >= 0) {
+    // Make a shared worker that looks like a worker
+    var worker = new SharedWorker(worker_url, "name" + ++shared_worker_count);
+    worker.port.onmessage = function(evt) {
+      worker.onmessage(evt);
+    };
+    worker.postMessage = function(msg, port) {
+      worker.port.postMessage(msg, port);
+    };
+    return worker;
+  } else {
+    return new Worker(worker_url);
+  }
+}
+
 function onSuccess()
 {
   setTimeout(onFinished, 0, "OK");
 }
 
 function onFailure() {
   setTimeout(onFinished, 0, "FAIL");
 }
 
 function onFinished(result) {
   var statusPanel = document.getElementById("statusPanel");
   if (statusPanel) {
     statusPanel.innerHTML = result;
   }
 
   var cookie = "status=" + result + "; path=/";
   document.cookie = cookie;
 }