Clean up copy&paste in confirmation dialogs for prefs

chrome/browser/resources/options/do_not_track_confirm_overlay.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.
-
-cr.define('options', function() {
-  var SettingsDialog = options.SettingsDialog;
-
-  /**
-   * DoNotTrackConfirmOverlay class
-   * Dialog to confirm that the user really wants to enable Do Not Track.
-   * @extends {SettingsDialog}
-   */
-  function DoNotTrackConfirmOverlay() {
-    SettingsDialog.call(
-        this,
-        'doNotTrackConfirm',
-        loadTimeData.getString('doNotTrackConfirmOverlayTabTitle'),
-        'do-not-track-confirm-overlay',
-        $('do-not-track-confirm-ok'),
-        $('do-not-track-confirm-cancel'));
-  };
-
-  cr.addSingletonGetter(DoNotTrackConfirmOverlay);
-
-  DoNotTrackConfirmOverlay.prototype = {
-    __proto__: SettingsDialog.prototype,
-
-    /** @inheritDoc */
-    handleConfirm: function() {
-      SettingsDialog.prototype.handleConfirm.call(this);
-      Preferences.setBooleanPref('enable_do_not_track', true, true);
-    },
-
-    /** @inheritDoc */
-    handleCancel: function() {
-      SettingsDialog.prototype.handleCancel.call(this);
-      $('do-not-track-enabled').checked = false;
-    },
-  };
-
-  // Export
-  return {
-    DoNotTrackConfirmOverlay: DoNotTrackConfirmOverlay
-  };
-});