Ensure History > Recent Tabs restore preserves window disposition.

chrome/browser/ui/toolbar/recent_tabs_sub_menu_model.cc

 // Copyright 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.
 
 #include "chrome/browser/ui/toolbar/recent_tabs_sub_menu_model.h"
 
 #include <stddef.h>
 
 #include "base/bind.h"
 #include "base/metrics/histogram_macros.h"
@@ skipping 446 matching lines @@
           auto& tab =
               static_cast<const sessions::TabRestoreService::Tab&>(*entry);
           const sessions::SerializedNavigationEntry& current_navigation =
               tab.navigations.at(tab.current_navigation_index);
           BuildLocalTabItem(entry->id, current_navigation.title(),
                             current_navigation.virtual_url(),
                             ++last_local_model_index_);
           break;
         }
         case sessions::TabRestoreService::WINDOW: {
+          // TODO(chrisha): Make this menu entry better. When windows contain a
+          // single tab, display that tab directly in the menu. Otherwise, offer
+          // a hover over or alternative mechanism for seeing which tabs were in
+          // the window.
           BuildLocalWindowItem(
               entry->id,
               static_cast<const sessions::TabRestoreService::Window&>(*entry)
                   .tabs.size(),
               ++last_local_model_index_);
           break;
         }
       }
       ++added_count;
     }
@@ skipping 284 matching lines @@
 void RecentTabsSubMenuModel::OnForeignSessionUpdated(
     syncer::SyncService* sync) {
   ClearTabsFromOtherDevices();
 
   BuildTabsFromOtherDevices();
 
   ui::MenuModelDelegate* menu_model_delegate = GetMenuModelDelegate();
   if (menu_model_delegate)
     menu_model_delegate->OnMenuStructureChanged();
 }