Respect policy for list of startup pages

chrome/browser/resources/options2/browser_options.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 OptionsPage = options.OptionsPage;
   var ArrayDataModel = cr.ui.ArrayDataModel;
   var RepeatingButton = cr.ui.RepeatingButton;
 
   //
@@ skipping 62 matching lines @@
       // Internet connection section (ChromeOS only).
       if (cr.isChromeOS) {
         $('internet-options-button').onclick = function(event) {
           OptionsPage.navigateToPage('internet');
           chrome.send('coreOptionsUserMetricsAction',
               ['Options_InternetOptions']);
         };
       }
 
       // On Startup section.
-      $('startup-set-pages').onclick = function() {
+      var startupSetPagesLink = $('startup-set-pages');
+      const showPagesValue = Number($('startup-show-pages').value);
+
+      Preferences.getInstance().addEventListener('session.restore_on_startup',
+                                                 function(event) {
+        startupSetPagesLink.disabled = event.value['disabled'] &&
+                                       event.value['value'] != showPagesValue;
+      });
+
+      startupSetPagesLink.onclick = function() {
         OptionsPage.navigateToPage('startup');
       };
 
       this.sessionRestoreEnabled_ = templateData.enable_restore_session_state;
       if (this.sessionRestoreEnabled_) {
         $('old-startup-last-text').hidden = true;
         $('new-startup-last-text').hidden = false;
       }
 
       // Appearance section.
@@ skipping 1125 matching lines @@
     BrowserOptions.getLoggedInUsername = function() {
       return BrowserOptions.getInstance().username_;
     };
   }
 
   // Export
   return {
     BrowserOptions: BrowserOptions
   };
 });