Enabled a number of worker tests on various platforms.

chrome/test/data/workers/worker_common.js

Index: chrome/test/data/workers/worker_common.js
diff --git a/chrome/test/data/workers/worker_common.js b/chrome/test/data/workers/worker_common.js
index 583c6a55eb0ddb2d1f7fbf814951f22f9e28e5b8..8caa6227fa97efa2c34ed3ceabc211130344bd5d 100644
--- a/chrome/test/data/workers/worker_common.js
+++ b/chrome/test/data/workers/worker_common.js
@@ -1,3 +1,14 @@
+if (!self.postMessage) {
+  // This is a shared worker - mimic dedicated worker APIs
+  onconnect = function(event) {
+    event.ports[0].onmessage = function(e) {
+      self.onmessage(e);
+    };
+    self.postMessage = function(msg, ports) {
+      event.ports[0].postMessage(msg, ports);
+    };
+  };
+}
 onmessage = function(evt) {
   if (evt.data == "ping")
     postMessage("pong");