Support additional mash shelf alignments.

ash/mus/shelf_delegate_mus.h

Index: ash/mus/shelf_delegate_mus.h
diff --git a/ash/mus/shelf_delegate_mus.h b/ash/mus/shelf_delegate_mus.h
index 47364fce7e8b9bfaa66f31ce7ed152de50c2a30e..d5da3d720b6a147502d5c15311f48129e9f97300 100644
--- a/ash/mus/shelf_delegate_mus.h
+++ b/ash/mus/shelf_delegate_mus.h
@@ -8,6 +8,8 @@
 #include <map>
 
 #include "ash/shelf/shelf_delegate.h"
+#include "ash/shelf/shelf_types.h"
+#include "mash/wm/public/interfaces/shelf_layout.mojom.h"
 #include "mash/wm/public/interfaces/user_window_controller.mojom.h"
 #include "mojo/public/cpp/bindings/binding.h"
 
@@ -27,6 +29,8 @@ class ShelfDelegateMus : public ShelfDelegate,
   // ShelfDelegate:
   void OnShelfCreated(Shelf* shelf) override;
   void OnShelfDestroyed(Shelf* shelf) override;
+  void OnAlignmentChanged(ShelfAlignment alignment) override;
+  void OnAutoHideBehaviorChanged(ShelfAutoHideBehavior auto_hide) override;
   ShelfID GetShelfIDForAppID(const std::string& app_id) override;
   bool HasShelfIDToAppIDMapping(ShelfID id) const override;
   const std::string& GetAppIDForShelfID(ShelfID id) override;
@@ -44,7 +48,9 @@ class ShelfDelegateMus : public ShelfDelegate,
   void OnUserWindowFocusChanged(uint32_t window_id, bool has_focus) override;
 
   ShelfModel* model_;
+  Shelf* shelf_;
 
+  mash::wm::mojom::ShelfLayoutPtr shelf_layout_;
   mash::wm::mojom::UserWindowControllerPtr user_window_controller_;
   mojo::Binding<mash::wm::mojom::UserWindowObserver> binding_;
   std::map<uint32_t, ShelfID> window_id_to_shelf_id_;