Drastically reduce the number of redraws when editing content settings.

chrome/browser/resources/options/content_settings.js

 // Copyright (c) 2010 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 OptionsPage = options.OptionsPage;
 
   //////////////////////////////////////////////////////////////////////////////
   // ContentSettings class:
@@ skipping 81 matching lines @@
    * @param {string} type The content type that we are setting exceptions for.
    * @param {Array} list An array of pairs, where the first element of each pair
    *     is the filter string, and the second is the setting (allow/block).
    */
   ContentSettings.setExceptions = function(type, list) {
     var exceptionsList =
         document.querySelector('div[contentType=' + type + ']' +
                                ' list[mode=normal]');
 
     exceptionsList.reset();
-    for (var i = 0; i < list.length; i++) {
-      exceptionsList.addException(list[i]);
-    }
-    exceptionsList.redraw();
+    exceptionsList.addExceptions(list);

[arv (Not doing code reviews), 2011/01/12 00:42:32]

You could also have used startBatchUpdates() and endBatchUpdates()

   };
 
   ContentSettings.setOTRExceptions = function(type, list) {
     var exceptionsList =
         document.querySelector('div[contentType=' + type + ']' +
                                ' list[mode=otr]');
 
     exceptionsList.parentNode.classList.remove('hidden');
 
     exceptionsList.reset();
-    for (var i = 0; i < list.length; i++) {
-      exceptionsList.addException(list[i]);
-    }
-    exceptionsList.redraw();
+    exceptionsList.addExceptions(list);
   };
 
   /**
    * Sets the initial value for the Third Party Cookies checkbox.
    * @param {boolean=} block True if we are blocking third party cookies.
    */
   ContentSettings.setBlockThirdPartyCookies = function(block) {
     $('block-third-party-cookies').checked = block;
   };
 
@@ skipping 13 matching lines @@
                                'list[mode=' + mode + ']');
     exceptionsList.patternValidityCheckComplete(pattern, valid);
   };
 
   // Export
   return {
     ContentSettings: ContentSettings
   };
 
 });