The "Update Chrome" menu item should appear in addition to the About menu.

app/menus/simple_menu_model.cc

 // 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.
 
 #include "app/menus/simple_menu_model.h"
 
 #include "app/l10n_util.h"
 #include "third_party/skia/include/core/SkBitmap.h"
 
 static const int kSeparatorId = -1;
 
 namespace menus {
 
 struct SimpleMenuModel::Item {
   int command_id;
   string16 label;
   SkBitmap icon;
   ItemType type;
   int group_id;
   MenuModel* submenu;
   ButtonMenuItemModel* button_model;
 };
 
 ////////////////////////////////////////////////////////////////////////////////
 // SimpleMenuModel::Delegate, public:
 
+bool SimpleMenuModel::Delegate::IsCommandIdVisible(int command_id) const {
+  return true;
+}
+
 bool SimpleMenuModel::Delegate::IsLabelForCommandIdDynamic(
     int command_id) const {
   return false;
 }
 
 string16 SimpleMenuModel::Delegate::GetLabelForCommandId(int command_id) const {
   return string16();
 }
 
 void SimpleMenuModel::Delegate::CommandIdHighlighted(int command_id) {
@@ skipping 206 matching lines @@
 }
 
 bool SimpleMenuModel::IsEnabledAt(int index) const {
   int command_id = GetCommandIdAt(index);
   if (!delegate_ || command_id == kSeparatorId ||
       items_.at(FlipIndex(index)).button_model)
     return true;
   return delegate_->IsCommandIdEnabled(command_id);
 }
 
+bool SimpleMenuModel::IsVisibleAt(int index) const {
+  int command_id = GetCommandIdAt(index);
+  if (!delegate_ || command_id == kSeparatorId ||
+      items_.at(FlipIndex(index)).button_model)
+    return true;
+  return delegate_->IsCommandIdVisible(command_id);
+}
+
 void SimpleMenuModel::HighlightChangedTo(int index) {
   if (delegate_)
     delegate_->CommandIdHighlighted(GetCommandIdAt(index));
 }
 
 void SimpleMenuModel::ActivatedAt(int index) {
   if (delegate_)
     delegate_->ExecuteCommand(GetCommandIdAt(index));
 }
 
 MenuModel* SimpleMenuModel::GetSubmenuModelAt(int index) const {
   return items_.at(FlipIndex(index)).submenu;
 }
 
+int SimpleMenuModel::FlipIndex(int index) const {
+  return index;
+}
+
 ////////////////////////////////////////////////////////////////////////////////
 // SimpleMenuModel, Private:
 
 void SimpleMenuModel::AppendItem(const Item& item) {
   ValidateItem(item);
   items_.push_back(item);
 }
 
 void SimpleMenuModel::InsertItemAtIndex(const Item& item, int index) {
   ValidateItem(item);
   items_.insert(items_.begin() + FlipIndex(index), item);
 }
 
 void SimpleMenuModel::ValidateItem(const Item& item) {
 #ifndef NDEBUG
   if (item.type == TYPE_SEPARATOR) {
     DCHECK_EQ(item.command_id, kSeparatorId);
   } else {
     DCHECK_GE(item.command_id, 0);
   }
 #endif  // NDEBUG
 }
 
 }  // namespace menus