Only allows extensions to create HTML notifications.

chrome/test/data/extensions/api_test/notifications/has_permission_prefs/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 notification = null;
 
-// Shows the notification window using the specified URL.
-// Control continues at onNotificationDone().
-function showNotification(url) {
-  notification = window.webkitNotifications.createHTMLNotification(url);
+function showHTMLNotification() {
+  // createHTMLNotification is not exposed even when the web page permission
+  // is granted.
+  if (window.webkitNotifications.createHTMLNotification)
+    chrome.test.fail("createHTMLNotification is found.");
+  else
+    chrome.test.succeed();
+}
+
+function showTextNotification() {
+  notification = window.webkitNotifications.createNotification(
+      "", "Foo", "This is text notification.");
   notification.onerror = function() {
     chrome.test.fail("Failed to show notification.");
   };
+  notification.ondisplay = function() {
+    chrome.test.succeed();
+  };
   notification.show();
 }
 
-// Called by the notification when it is done with its tests.
-function onNotificationDone(notificationWindow) {
-  var views = chrome.extension.getViews();
-  chrome.test.assertEq(2, views.length);
-  notificationWindow.onunload = function() {
-    chrome.test.succeed();
-  }
-  notification.cancel();
-}
-
 chrome.test.runTests([
   function hasPermission() {
     chrome.test.assertEq(0,  // allowed
                          webkitNotifications.checkPermission());
     chrome.test.succeed();
   },
-  function absoluteURL() {
-    showNotification(chrome.extension.getURL("notification.html"));
+  function htmlNotification() {
+    showHTMLNotification();

[Mihai Parparita -not on Chrome, 2012/07/26 23:59:05]

You might as well inline the test functions.

[jianli, 2012/07/27 00:34:10]

Done.

   },
-  function relativeURL() {
-    showNotification("notification.html");
+  function textNotification() {
+    showTextNotification();
   }
 ]);