Reduce number of expensive calls to List.redraw() during load of settings page.

chrome/browser/resources/options2/content_settings_exceptions_area.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.contentSettings', function() {
   /** @const */ var InlineEditableItemList = options.InlineEditableItemList;
   /** @const */ var InlineEditableItem = options.InlineEditableItem;
   /** @const */ var ArrayDataModel = cr.ui.ArrayDataModel;
 
   /**
@@ skipping 504 matching lines @@
     __proto__: OptionsPage.prototype,
 
     initializePage: function() {
       OptionsPage.prototype.initializePage.call(this);
 
       var exceptionsLists = this.pageDiv.querySelectorAll('list');
       for (var i = 0; i < exceptionsLists.length; i++) {
         options.contentSettings.ExceptionsList.decorate(exceptionsLists[i]);
       }
 
-      ContentSettingsExceptionsArea.hideOTRLists();
+      ContentSettingsExceptionsArea.hideOTRLists(false);
 
       // If the user types in the URL without a hash, show just cookies.
       this.showList('cookies');
 
       $('content-settings-exceptions-overlay-confirm').onclick =
           OptionsPage.closeOverlay.bind(OptionsPage);
     },
 
     /**
      * Shows one list and hides all others.
@@ skipping 21 matching lines @@
       var hash = location.hash;
       if (hash)
         this.showList(hash.slice(1));
     },
   };
 
   /**
    * Called when the last incognito window is closed.
    */
   ContentSettingsExceptionsArea.OTRProfileDestroyed = function() {
-    this.hideOTRLists();
+    this.hideOTRLists(true);
   };
 
   /**
-   * Clears and hides the incognito exceptions lists.
+   * Hides the incognito exceptions lists and optionally clears them as well.
+   * @param {boolean} clear Whether to clear the lists.
    */
-  ContentSettingsExceptionsArea.hideOTRLists = function() {
+  ContentSettingsExceptionsArea.hideOTRLists = function(clear) {
     var otrLists = document.querySelectorAll('list[mode=otr]');
 
     for (var i = 0; i < otrLists.length; i++) {
-      otrLists[i].reset();
       otrLists[i].parentNode.hidden = true;
+      if (clear)
+        otrLists[i].reset();
     }
   };
 
   return {
     ExceptionsListItem: ExceptionsListItem,
     ExceptionsAddRowListItem: ExceptionsAddRowListItem,
     ExceptionsList: ExceptionsList,
     ContentSettingsExceptionsArea: ContentSettingsExceptionsArea,
   };
 });