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

ash/common/shelf/shelf_view.h

Index: ash/common/shelf/shelf_view.h
diff --git a/ash/common/shelf/shelf_view.h b/ash/common/shelf/shelf_view.h
index 3f1858b5cdba4a162882e9eafa8b03466589b55e..073f2f10c3d98b6c8cd3a77168bd1c8693f1a2f2 100644
--- a/ash/common/shelf/shelf_view.h
+++ b/ash/common/shelf/shelf_view.h
@@ -292,6 +292,15 @@ class ASH_EXPORT ShelfView : public views::View,
   void OnSetShelfItemDelegate(ShelfID id,
                               ShelfItemDelegate* item_delegate) override;
 
+  // Handles the result of an item selection, records the |action| taken and
+  // optionally shows an application menu with the given |menu_items|.
+  void AfterItemSelected(const ShelfItem& item,
+                         views::Button* sender,
+                         std::unique_ptr<ui::Event> event,
+                         views::InkDrop* ink_drop,
+                         ShelfAction action,
+                         ShelfItemDelegate::MenuItemList menu_items);
+
   // Show a list of all running items for this shelf |item|; it only shows a
   // menu if there are multiple running items. |source| specifies the view
   // responsible for showing the menu, and the bubble will point towards it.