Add a pref checkbox to enable/disable screen lock for ChromeOs.

chrome/browser/resources/options/personal_options.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;
 
   //
   // PersonalOptions class
@@ skipping 76 matching lines @@
       }
 
       if (cr.isMac || cr.isWindows || cr.isChromeOS) {
         $('themes_reset').onclick = function(event) {
           chrome.send('themesReset');
         };
         $('themes-gallery').onclick = function(event) {
           chrome.send('themesGallery');
         }
       }
+
+      if (cr.isChromeOS) {
+        chrome.send('loadAccountPicture');
+      }
     },
 
     syncStatusCallback_: function(statusString) {
       $('synced_to_user_with_time').textContent = statusString;
     },
 
     setGtkThemeButtonEnabled_: function(enabled) {
       if (!cr.isChromeOS && navigator.platform.match(/linux|BSD/i)) {
         $('themes_GTK_button').disabled = !enabled;
       }
@@ skipping 34 matching lines @@
   };
 
   PersonalOptions.setGtkThemeButtonEnabled = function(enabled) {
     PersonalOptions.getInstance().setGtkThemeButtonEnabled_(enabled);
   };
 
   PersonalOptions.setClassicThemeButtonEnabled = function(enabled) {
     PersonalOptions.getInstance().setClassicThemeButtonEnabled_(enabled);
   };
 
+  PersonalOptions.setAccountPicture = function(image) {
+    $('account-picture').src = image;
+  }
+
   // Export
   return {
     PersonalOptions: PersonalOptions
   };
 
 });