mash: Migrate shelf menus to wm common types

ash/shelf/shelf_alignment_menu.h

Index: ash/shelf/shelf_alignment_menu.h
diff --git a/ash/shelf/shelf_alignment_menu.h b/ash/shelf/shelf_alignment_menu.h
index 98d1eeff2546fe2d3cca76c8954a84826985ad34..da628c4e73c63da74891b575c0e162f049eea51e 100644
--- a/ash/shelf/shelf_alignment_menu.h
+++ b/ash/shelf/shelf_alignment_menu.h
@@ -11,13 +11,13 @@
 
 namespace ash {
 
-class Shelf;
+class WmShelf;
 
-// Submenu for choosing the alignment of the launcher.
+// Submenu for choosing the alignment of the shelf.
 class ASH_EXPORT ShelfAlignmentMenu : public ui::SimpleMenuModel,
                                       public ui::SimpleMenuModel::Delegate {
  public:
-  explicit ShelfAlignmentMenu(Shelf* shelf);
+  explicit ShelfAlignmentMenu(WmShelf* wm_shelf);
   ~ShelfAlignmentMenu() override;
 
   // ui::SimpleMenuModel::Delegate overrides:
@@ -35,7 +35,7 @@ class ASH_EXPORT ShelfAlignmentMenu : public ui::SimpleMenuModel,
     MENU_ALIGN_BOTTOM,
   };
 
-  Shelf* shelf_;
+  WmShelf* wm_shelf_;
 
   DISALLOW_COPY_AND_ASSIGN(ShelfAlignmentMenu);
 };