Move another bunch of extension API tests to manifest_version 2.

chrome/test/data/extensions/api_test/content_scripts/extension_process/background.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.
+
+var numPings = 0;
+chrome.extension.onRequest.addListener(function(data) {
+  if (data != "ping")
+    chrome.test.fail("Unexpected request: " + JSON.stringify(data));
+
+  if (++numPings == 2)
+    chrome.test.notifyPass();
+});
+
+chrome.test.getConfig(function(config) {
+  var test_file_url = "http://localhost:PORT/files/extensions/test_file.html"
+      .replace(/PORT/, config.testServer.port);
+
+  // Add a window.
+  var w = window.open(test_file_url);
+
+  // Add an iframe.
+  var iframe = document.createElement("iframe");
+  iframe.src = test_file_url;
+  document.getElementById("iframeContainer").appendChild(iframe);
+});