Options: maintain history entries on the parent frame.

chrome/browser/resources/options/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.
 
 var AddLanguageOverlay = options.AddLanguageOverlay;
 var AlertOverlay = options.AlertOverlay;
 var AutofillEditAddressOverlay = options.AutofillEditAddressOverlay;
 var AutofillEditCreditCardOverlay = options.AutofillEditCreditCardOverlay;
 var AutofillOptions = options.AutofillOptions;
 var AutomaticSettingsResetBanner = options.AutomaticSettingsResetBanner;
@@ skipping 213 matching lines @@
   AutomaticSettingsResetBanner.getInstance().initialize();
   OptionsPage.initialize();
 
   var path = document.location.pathname;
 
   if (path.length > 1) {
     // Skip starting slash and remove trailing slash (if any).
     var pageName = path.slice(1).replace(/\/$/, '');
     OptionsPage.showPageByName(pageName, true, {replaceState: true});
   } else {
-    OptionsPage.showDefaultPage();
+    OptionsPage.showDefaultPage({replaceState: true});
   }
 
   var subpagesNavTabs = document.querySelectorAll('.subpages-nav-tabs');
   for (var i = 0; i < subpagesNavTabs.length; i++) {
     subpagesNavTabs[i].onclick = function(event) {
       OptionsPage.showTab(event.srcElement);
     };
   }
 
   window.setTimeout(function() {
@@ skipping 12 matching lines @@
   options.OptionsPage.willClose();
 };
 
 /**
  * Listener for the |popstate| event.
  * @param {Event} e The |popstate| event.
  */
 window.onpopstate = function(e) {
   options.OptionsPage.setState(e.state);
 };