[options2] Fix issue when deleting a user and pressing back.

chrome/browser/resources/options2/options_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() {
   /////////////////////////////////////////////////////////////////////////////
   // OptionsPage class:
 
   /**
    * Base class for options page.
@@ skipping 54 matching lines @@
    */
   OptionsPage.navigateToPage = function(pageName) {
     this.showPageByName(pageName, true);
   };
 
   /**
    * Shows a registered page. This handles both top-level and overlay pages.
    * @param {string} pageName Page name.
    * @param {boolean} updateHistory True if we should update the history after
    *     showing the page.
-   * @param {Object=} opt_propertyBag An optional bag of properties including
-   *     replaceState (if history state should be replaced instead of pushed).
+   * @param {{replaceState: (boolean|undefined), hash: (string|undefined)}=}
+   *     opt_historyOptions An optional bag of history behavior modifiers.
    * @private
    */
   OptionsPage.showPageByName = function(pageName,
                                         updateHistory,
-                                        opt_propertyBag) {
+                                        opt_historyOptions) {
     // If |opt_propertyBag| is non-truthy, homogenize to object.
-    opt_propertyBag = opt_propertyBag || {};
+    opt_historyOptions = opt_historyOptions || {};
 
     // Find the currently visible root-level page.
     var rootPage = null;
     for (var name in this.registeredPages) {
       var page = this.registeredPages[name];
       if (page.visible && !page.parentPage) {
         rootPage = page;
         break;
       }
     }
 
     // Find the target page.
     var targetPage = this.registeredPages[pageName.toLowerCase()];
     if (!targetPage || !targetPage.canShowPage()) {
       // If it's not a page, try it as an overlay.
       if (!targetPage && this.showOverlay_(pageName, rootPage)) {
-        if (updateHistory)
-          this.updateHistoryState_(!!opt_propertyBag.replaceState);
+        if (updateHistory) {
+          this.updateHistoryState_(!!opt_historyOptions.replaceState,
+                                   {hash: opt_historyOptions.hash});
+        }
         return;
       } else {
         targetPage = this.getDefaultPage();
       }
     }
 
     pageName = targetPage.name.toLowerCase();
     var targetPageWasVisible = targetPage.visible;
 
     // Determine if the root page is 'sticky', meaning that it
@@ skipping 23 matching lines @@
     for (var i = 0; i < allPageNames.length; ++i) {
       var name = allPageNames[i];
       var page = this.registeredPages[name] ||
                  this.registeredOverlayPages[name];
       if (!page.parentPage && isRootPageLocked)
         continue;
       page.visible = name == pageName || page.isAncestorOfPage(targetPage);
     }
 
     // Update the history and current location.
-    if (updateHistory)
-      this.updateHistoryState_(!!opt_propertyBag.replaceState);
+    if (updateHistory) {
+      this.updateHistoryState_(
+          !!opt_historyOptions.replaceState, {hash: opt_historyOptions.hash});
+    }
 
     // Update tab title.
     this.setTitle_(targetPage.title);
 
     // Notify pages if they were shown.
     for (var i = 0; i < allPageNames.length; ++i) {
       var name = allPageNames[i];
       var page = this.registeredPages[name] ||
                  this.registeredOverlayPages[name];
       if (!page.parentPage && isRootPageLocked)
@@ skipping 40 matching lines @@
     var path = window.location.pathname + window.location.hash;
     if (path)
       path = path.slice(1).replace(/\/(?:#|$)/, '');  // Remove trailing slash.
     // The page is already in history (the user may have clicked the same link
     // twice). Do nothing.
     if (path == page.name &&
         !document.documentElement.classList.contains('loading')) {
       return;
     }
 
-    var hash = opt_params && opt_params.ignoreHash ? '' : window.location.hash;
+    opt_params = opt_params || {};
+    assert(!(opt_params.ignoreHash && opt_params.hash),
+           'mutually exclusive hash params given to updateHistoryState_');
+
+    var hash = '';
+    if (!opt_params.ignoreHash) {
+      if (opt_params.hash) {
+        assert('#' == opt_params.hash.substr(0, 1));
+        hash = opt_params.hash;
+      } else {
+        hash = window.location.hash;
+      }
+    }
 
     // If settings are embedded, tell the outer page to set its "path" to the
     // inner frame's path.
     var outerPath = (page == this.getDefaultPage() ? '' : page.name) + hash;
     uber.invokeMethodOnParent('setPath', {path: outerPath});
 
     // If there is no path, the current location is chrome://settings/.
     // Override this with the new page.
     var historyFunction = path && !replace ? window.history.pushState :
                                              window.history.replaceState;
@@ skipping 681 matching lines @@
     canShowPage: function() {
       return true;
     },
   };
 
   // Export
   return {
     OptionsPage: OptionsPage
   };
 });