Revert of mash: Fix MusPropertyMirrorAsh for owned properties; add test.

ash/public/cpp/shelf_item_types.cc

Index: ash/public/cpp/shelf_item_types.cc
diff --git a/ash/public/cpp/shelf_item_types.cc b/ash/public/cpp/shelf_item_types.cc
deleted file mode 100644
index bb6a80c5f5e9534d8336e53229e4922b6c6248d5..0000000000000000000000000000000000000000
--- a/ash/public/cpp/shelf_item_types.cc
+++ /dev/null
@@ -1,13 +0,0 @@
-// Copyright 2014 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#include "ash/public/cpp/shelf_item_types.h"
-
-namespace ash {
-
-ShelfItem::ShelfItem() {}
-ShelfItem::ShelfItem(const ShelfItem& shelf_item) = default;
-ShelfItem::~ShelfItem() {}
-
-}  // namespace ash