Factor tab context menu into a shared model and fix mac and win to use it. Im...

chrome/browser/cocoa/menu_controller.mm

 // Copyright (c) 2009 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.
 
 #import "chrome/browser/cocoa/menu_controller.h"
 
 #include "app/l10n_util_mac.h"
 #include "app/menus/simple_menu_model.h"
 #include "base/logging.h"
 #include "base/sys_string_conversions.h"
@@ skipping 78 matching lines @@
     [item setTarget:nil];
     [item setAction:nil];
     menus::MenuModel* submenuModel = model->GetSubmenuModelAt(modelIndex);
     NSMenu* submenu =
         [self menuFromModel:(menus::SimpleMenuModel*)submenuModel];
     [item setSubmenu:submenu];
   } else {
     // The MenuModel works on indexes so we can't just set the command id as the
     // tag like we do in other menus. Also set the represented object to be
     // the model so hierarchical menus check the correct index in the correct
-    // model.
+    // model. Setting the target to |self| allows this class to participate
+    // in validation of the menu items.
     [item setTag:modelIndex];
     [item setTarget:self];
     NSValue* modelObject = [NSValue valueWithPointer:model];
     [item setRepresentedObject:modelObject];  // Retains |modelObject|.
   }
   [menu insertItem:item atIndex:index];
 }
 
 // Called before the menu is to be displayed to update the state (enabled,
 // radio, etc) of each item in the menu.
@@ skipping 26 matching lines @@
   DCHECK(model);
   if (model);
     model->ActivatedAt(modelIndex);
 }
 
 - (NSMenu*)menu {
   return menu_.get();
 }
 
 @end