Move another set of extension tests to manifest_version 2

chrome/test/data/extensions/api_test/tabs/on_updated/iframeNavigated/frame2.js

+// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+window.onload = function() {
+  // Navigate after onload so that 'complete' status will fire.
+  setTimeout(function() {
+    location.href = "iframe3.html";
+  }, 0);
+}