Fix crash in AppNotifyChannelSetup when incognito profiles are used.

chrome/test/data/extensions/api_test/app_notifications/test.js

+// 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 error = "This API is not accessible by 'split' mode extensions" +
+    " in incognito windows.";
+
+chrome.test.runTests([
+  function notify() {
+    chrome.experimental.app.notify(
+        {}, chrome.test.callbackFail(error));
+  },
+
+  function clearAllNotifications() {
+    chrome.experimental.app.clearAllNotifications(
+        {}, chrome.test.callbackFail(error));
+  }
+]);