Enable runtime switching between ChromeVox and ChromeVox next via command line.

chrome/browser/resources/chromeos/chromevox2/cvox2/background/background.extjs

-// Copyright 2014 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.
-
-// Include test fixture.
-GEN_INCLUDE(['../../../chromevox/testing/chromevox_e2e_test_base.js']);
-
-/**
- * Test fixture for cvox2.Background.
- * @constructor
- * @extends {ChromeVoxE2ETest}
- */
-function BackgroundTest() {}
-
-BackgroundTest.prototype = {
-  __proto__: ChromeVoxE2ETest.prototype,
-
-  /** @override */
-  setUp: function() {
-    this.mockTts = new MockTts();
-    cvox.ChromeVox.tts = this.mockTts;
-  }
-};
-
-/**
- * Mock tts class.
- * @constructor
- * @extends {cvox.TtsInterface}
- */
-var MockTts = function() {
-};
-
-MockTts.prototype = {
-  /** Tracks all spoken text. @type {!Array.<string>} */
-  utterances: [],
-
-  /** @override */
-  speak: function(textString, queueMode, properties) {
-    this.utterances.push(textString);
-  },
-
-  /**
-   * Checks to see if a string was spoken.
-   * @param {string} textString The string to check.
-   * @return {boolean} True if the string was spoken (possibly as part of a
-   * larger utterance).
-   */
-  checkIfSubstringWasSpoken: function(textString) {
-    return this.utterances.some(function(t) {
-      return t.indexOf(textString) != -1;
-    });
-  }
-};
-
-/** Tests that ChromeVox classic is in this context. */
-SYNC_TEST_F('BackgroundTest', 'ClassicNamespaces', function() {
-  assertEquals('object', typeof(cvox));
-  assertEquals('function', typeof(cvox.ChromeVoxBackground));
-});
-
-/** Tests that ChromeVox next is in this context. */
-SYNC_TEST_F('BackgroundTest', 'NextNamespaces', function() {
-  assertEquals('object', typeof(cvox2));
-  assertEquals('function', typeof(cvox2.Background));
-});
-
-/** Tests that ChromeVox reads the desktop tree. */
-TEST_F('BackgroundTest', 'DesktopFocus', function() {
-  function findStatusTray(root) {
-    if (root.role == chrome.automation.RoleType.button &&
-        root.attributes.name &&
-        root.attributes.name.indexOf('Status tray') != -1) {
-      return root;
-    }
-    for (var i = 0; i < root.children().length; i++) {
-      var found = findStatusTray(root.children()[i]);
-      if (found)
-        return found;
-    }
-    return null;
-  }
-
-  chrome.automation.getDesktop(function(root) {
-    var testButton = findStatusTray(root);
-    testButton.addEventListener(chrome.automation.EventType.focus,
-        function(e) {
-          var result =
-              cvox.ChromeVox.tts.checkIfSubstringWasSpoken('Status tray');
-          testDone([result, '']);
-        },
-        true);
-    testButton.focus();
-  });
-});