Guest mode causes certain settings to be hidden.

chrome/browser/resources/options/search_page.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() {
   /** @const */ var Page = cr.ui.pageManager.Page;
   /** @const */ var PageManager = cr.ui.pageManager.PageManager;
 
   /**
    * Encapsulated handling of a search bubble.
@@ skipping 169 matching lines @@
      * Update the UI to reflect whether we are in a search state.
      * @param {boolean} active True if we are on the search page.
      * @private
      */
     setSearchActive_: function(active) {
       // It's fine to exit if search wasn't active and we're not going to
       // activate it now.
       if (!this.searchActive_ && !active)
         return;
 
+      // Guest users should never have active search

[Evan Stade, 2014/08/19 17:49:13]

nit: final punctuation

[Mike Lerman, 2014/08/19 20:34:12]

Done.

+      if (loadTimeData.getBoolean('profileIsGuest'))
+        return;
+
       this.searchActive_ = active;
 
       if (active) {
         var hash = location.hash;
         if (hash) {
           this.searchField.value =
               decodeURIComponent(hash.slice(1).replace(/\+/g, ' '));
         } else if (!this.searchField.value) {
           // This should only happen if the user goes directly to
           // chrome://settings-frame/search
@@ skipping 53 matching lines @@
         }
       }
     },
 
     /**
      * Set the current search criteria.
      * @param {string} text Search text.
      * @private
      */
     setSearchText_: function(text) {
+      // Guest users should never have search text.
+      if (loadTimeData.getBoolean('profileIsGuest'))
+        return;
+
       // Prevent recursive execution of this method.
       if (this.insideSetSearchText_) return;
       this.insideSetSearchText_ = true;
 
       // Cleanup the search query string.
       text = SearchPage.canonicalizeQuery(text);
 
       // Set the hash on the current page, and the enclosing uber page. Only do
       // this if the page is not current. See https://crbug.com/401004.
       var hash = text ? '#' + encodeURIComponent(text) : '';
@@ skipping 295 matching lines @@
     // Trim beginning and ending whitespace.
     return text.replace(/^\s+|\s+$/g, '');
   };
 
   // Export
   return {
     SearchPage: SearchPage
   };
 
 });