mash: Use mojo for ShelfItemDelegate and [app] MenuItem.

ash/common/shelf/shelf_model.h

Index: ash/common/shelf/shelf_model.h
diff --git a/ash/common/shelf/shelf_model.h b/ash/common/shelf/shelf_model.h
index a5f61e806ae84da5612fcdfb6c42fff62ea72da3..6c48843eb1c15b27c0a9d87e467700f588ad4226 100644
--- a/ash/common/shelf/shelf_model.h
+++ b/ash/common/shelf/shelf_model.h
@@ -10,12 +10,12 @@
 
 #include "ash/ash_export.h"
 #include "ash/common/shelf/shelf_item_types.h"
+#include "ash/public/interfaces/shelf.mojom.h"
 #include "base/macros.h"
 #include "base/observer_list.h"
 
 namespace ash {
 
-class ShelfItemDelegate;
 class ShelfModelObserver;
 
 // Model used for shelf items. Owns ShelfItemDelegates but does not create them.
@@ -76,11 +76,12 @@ class ASH_EXPORT ShelfModel {
   int item_count() const { return static_cast<int>(items_.size()); }
 
   // Set |item_delegate| for |id| and takes ownership.
-  void SetShelfItemDelegate(ShelfID id,
-                            std::unique_ptr<ShelfItemDelegate> item_delegate);
+  void SetShelfItemDelegate(
+      ShelfID id,
+      std::unique_ptr<mojom::ShelfItemDelegate> item_delegate);
 
   // Returns ShelfItemDelegate for |id|, or null if none exists.
-  ShelfItemDelegate* GetShelfItemDelegate(ShelfID id);
+  mojom::ShelfItemDelegate* GetShelfItemDelegate(ShelfID id);
 
   void AddObserver(ShelfModelObserver* observer);
   void RemoveObserver(ShelfModelObserver* observer);
@@ -100,7 +101,7 @@ class ASH_EXPORT ShelfModel {
   ShelfItems items_;
   base::ObserverList<ShelfModelObserver> observers_;
 
-  std::map<ShelfID, std::unique_ptr<ShelfItemDelegate>>
+  std::map<ShelfID, std::unique_ptr<mojom::ShelfItemDelegate>>
       id_to_item_delegate_map_;
 
   DISALLOW_COPY_AND_ASSIGN(ShelfModel);