MD Settings: Eliminate SettingsSubpageBrowsertest.

chrome/browser/resources/settings/settings_page/settings_page_visibility.js

-// Copyright 2015 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.
-
-/**
- * @fileoverview
- * Behavior controlling the visibility of Settings pages.
- *
- * Example:
- *   behaviors: [SettingsPageVisibility],
- */
-
-/**
- * Set this to true in tests before loading the page (e.g. in preLoad()) so that
- * pages do not initially get created. Set this to false BEFORE modifying
- * pageVisibility. NOTE: Changing this value after the DOM is loaded will not
- * trigger a visibility change, pageVisibility must be modified to trigger data
- * binding events.
- * @type {boolean}
- */
-var settingsHidePagesByDefaultForTest;
-
-/** @polymerBehavior */
-var SettingsPageVisibility = {
-  properties: {
-    /**
-     * Dictionary defining page visibility. If not set for a page, visibility
-     * will default to true, unless settingsHidePagesByDefaultForTest is set
-     * in which case visibility defaults to false.
-     * @type {Object<boolean>}
-     */
-    pageVisibility: {
-      type: Object,
-      value: function() { return {}; },
-    },
-  },
-
-  /**
-   * @param {boolean|undefined} visibility
-   * @return {boolean}
-   */
-  showPage: function(visibility) {
-    if (settingsHidePagesByDefaultForTest)
-      return visibility === true;
-    return visibility !== false;
-  },
-};