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

ash/common/shelf/wm_shelf.cc

Index: ash/common/shelf/wm_shelf.cc
diff --git a/ash/common/shelf/wm_shelf.cc b/ash/common/shelf/wm_shelf.cc
index 2a06cc21baa5039b55009c07e6ae45d745dd18c5..6d67c2ddab8a24a0acfb8d9e8da123d0faa6c5d1 100644
--- a/ash/common/shelf/wm_shelf.cc
+++ b/ash/common/shelf/wm_shelf.cc
@@ -6,7 +6,6 @@
 
 #include "ash/common/shelf/shelf_controller.h"
 #include "ash/common/shelf/shelf_delegate.h"
-#include "ash/common/shelf/shelf_item_delegate.h"
 #include "ash/common/shelf/shelf_layout_manager.h"
 #include "ash/common/shelf/shelf_locking_manager.h"
 #include "ash/common/shelf/shelf_model.h"
@@ -16,6 +15,7 @@
 #include "ash/common/wm_shell.h"
 #include "ash/common/wm_window.h"
 #include "ash/public/cpp/shell_window_ids.h"
+#include "ash/public/interfaces/shelf.mojom.h"
 #include "ash/root_window_controller.h"
 #include "ash/shelf/shelf_bezel_event_handler.h"
 #include "ash/shell.h"
@@ -27,6 +27,14 @@
 
 namespace ash {
 
+namespace {
+
+// A callback that does nothing after shelf item selection handling.
+void NoopCallback(ShelfAction,
+                  base::Optional<std::vector<mojom::MenuItemPtr>>) {}
+
+}  // namespace
+
 // WmShelf::AutoHideEventHandler -----------------------------------------------
 
 // Forwards mouse and gesture events to ShelfLayoutManager for auto-hide.
@@ -291,9 +299,12 @@ void WmShelf::LaunchShelfItem(int item_index) {
 void WmShelf::ActivateShelfItem(int item_index) {
   ShelfModel* shelf_model = WmShell::Get()->shelf_model();
   const ShelfItem& item = shelf_model->items()[item_index];
-  ShelfItemDelegate* item_delegate = shelf_model->GetShelfItemDelegate(item.id);
-  item_delegate->ItemSelected(ui::ET_KEY_RELEASED, ui::EF_NONE,
-                              display::kInvalidDisplayId, LAUNCH_FROM_UNKNOWN);
+  mojom::ShelfItemDelegate* item_delegate =
+      shelf_model->GetShelfItemDelegate(item.id);
+  std::unique_ptr<ui::Event> event = base::MakeUnique<ui::KeyEvent>(
+      ui::ET_KEY_RELEASED, ui::VKEY_UNKNOWN, ui::EF_NONE);
+  item_delegate->ItemSelected(std::move(event), display::kInvalidDisplayId,
+                              LAUNCH_FROM_UNKNOWN, base::Bind(&NoopCallback));
 }
 
 bool WmShelf::ProcessGestureEvent(const ui::GestureEvent& event) {