Remove ash's MaterialDesignController.

ash/material_design/material_design_controller.cc

Index: ash/material_design/material_design_controller.cc
diff --git a/ash/material_design/material_design_controller.cc b/ash/material_design/material_design_controller.cc
deleted file mode 100644
index 6f220e87b29f8a58953c08ac6001251d58c3e94c..0000000000000000000000000000000000000000
--- a/ash/material_design/material_design_controller.cc
+++ /dev/null
@@ -1,21 +0,0 @@
-// Copyright 2016 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/material_design/material_design_controller.h"
-
-#include <string>
-
-namespace ash {
-
-// static
-bool MaterialDesignController::IsShelfMaterial() {
-  return true;
-}
-
-// static
-bool MaterialDesignController::IsSystemTrayMenuMaterial() {
-  return true;
-}
-
-}  // namespace ash