Revert of Enable a11y audit for chrome://settings

chrome/browser/ui/webui/options/options_browsertest_base.js

-// Copyright (c) 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.
-
-/**
- * @constructor
- * @extends {testing.Test}
- */
-function OptionsBrowsertestBase() {}
-
-OptionsBrowsertestBase.prototype = {
-  __proto__: testing.Test.prototype,
-
-  /** @override */
-  runAccessibilityChecks: true,
-
-  /** @override */
-  accessibilityIssuesAreErrors: true,
-
-  /** @override */
-  setUp: function() {
-    // user-image-stream is a streaming video element used for capturing a
-    // user image during OOBE.
-    this.accessibilityAuditConfig.ignoreSelectors('videoWithoutCaptions',
-                                                  '.user-image-stream');
-  },
-};