Make NetworkMenuModel a ui::MenuModel again.

views/controls/menu/menu_model_adapter.cc

Index: views/controls/menu/menu_model_adapter.cc
diff --git a/views/controls/menu/menu_model_adapter.cc b/views/controls/menu/menu_model_adapter.cc
index 90a99dbcbab91352b72398e890c5afe0bc5941b6..e2c895d4349148823ef769d5ae9bccdccb90a06c 100644
--- a/views/controls/menu/menu_model_adapter.cc
+++ b/views/controls/menu/menu_model_adapter.cc
@@ -32,7 +32,11 @@ void MenuModelAdapter::BuildMenu(MenuItemView* menu) {
       menu->RemoveMenuItemAt(0);
   }
 
-  menu_map_.clear();
+  // Leave entries in the map if the menu is being shown.  This
+  // allows the map to find the menu model of submenus being closed
+  // so ui::MenuModel::MenuClosed() can be called.
+  if (!menu->GetMenuController())
+    menu_map_.clear();
   menu_map_[menu] = menu_model_;
 
   // Repopulate the menu.