Gut ash::MaterialDesignController, and remove the about:flags entry.

ash/common/system/date/system_info_default_view_unittest.cc

 // 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/common/system/date/system_info_default_view.h"
 #include "ash/common/system/tray/tray_constants.h"
-#include "ash/common/test/material_design_controller_test_api.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #include "ui/views/view.h"
 
 namespace ash {
 
 class SystemInfoDefaultViewTest : public testing::Test {
  public:
   SystemInfoDefaultViewTest() {}
 
  protected:
@@ skipping 51 matching lines @@
 TEST_F(SystemInfoDefaultViewTest, PreferredWidthGreaterThanThreeButtonWidths) {
   const int kPreferredWidth =
       kMenuButtonSize + (kSeparatorWidth + kMenuButtonSize) * 2 + 1;
   const int effective_width = CalculateDateViewWidth(kPreferredWidth);
 
   EXPECT_EQ(effective_width,
             kMenuButtonSize + (kSeparatorWidth + kMenuButtonSize) * 2);
 }
 
 }  // namespace ash