Make it so that allow_js_access: false can be used with background pages created by window.open.

chrome/test/data/extensions/api_test/app_background_page/no_js_manifest/content_script.js

Index: chrome/test/data/extensions/api_test/app_background_page/no_js_manifest/content_script.js
diff --git a/chrome/test/data/extensions/api_test/app_background_page/no_js_manifest/content_script.js b/chrome/test/data/extensions/api_test/app_background_page/no_js_manifest/content_script.js
new file mode 100644
index 0000000000000000000000000000000000000000..ba714c65319e54cc849e137c00abbc6bccb217b7
--- /dev/null
+++ b/chrome/test/data/extensions/api_test/app_background_page/no_js_manifest/content_script.js
@@ -0,0 +1,18 @@
+// Copyright (c) 2012 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 scriptMessageEvent = document.createEvent("Event");
+scriptMessageEvent.initEvent('scriptMessage', true, true);
+
+var pageToScriptTunnel = document.getElementById("pageToScriptTunnel");
+pageToScriptTunnel.addEventListener("scriptMessage", function() {
+  var data = JSON.parse(pageToScriptTunnel.innerText);
+  chrome.extension.sendRequest(data);
+});
+
+chrome.extension.onRequest.addListener(function(request) {
+  var scriptToPageTunnel = document.getElementById("scriptToPageTunnel");
+  scriptToPageTunnel.innerText = JSON.stringify(request);
+  scriptToPageTunnel.dispatchEvent(scriptMessageEvent);
+});