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

ash/common/ash_switches.cc

 // Copyright (c) 2012 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/ash_switches.h"
 
 #include "base/command_line.h"
 #include "base/sys_info.h"
 
 namespace ash {
@@ skipping 55 matching lines @@
 const char kAshEnableMirroredScreen[] = "ash-enable-mirrored-screen";
 
 // Enables the palette next to the status area.
 const char kAshForceEnablePalette[] = "ash-force-enable-palette";
 
 // Hides notifications that are irrelevant to Chrome OS device factory testing,
 // such as battery level updates.
 const char kAshHideNotificationsForFactory[] =
     "ash-hide-notifications-for-factory";
 
-// Specifies if Material Design elements in Chrome OS system UI are enabled.
-// Can be disabled / enabled / experimental allowing to launch incrementally.
-const char kAshMaterialDesign[] = "ash-md";
-const char kAshMaterialDesignDisabled[] = "disabled";
-const char kAshMaterialDesignEnabled[] = "enabled";
-const char kAshMaterialDesignExperimental[] = "experimental";
-
 // Enables the heads-up display for tracking touch points.
 const char kAshTouchHud[] = "ash-touch-hud";
 
 // (Most) Chrome OS hardware reports ACPI power button releases correctly.
 // Standard hardware reports releases immediately after presses.  If set, we
 // lock the screen or shutdown the system immediately in response to a press
 // instead of displaying an interactive animation.
 const char kAuraLegacyPowerButton[] = "aura-legacy-power-button";
 
 // Constrains the pointer movement within a root window on desktop.
 bool ConstrainPointerToRoot() {
   const char kAshConstrainPointerToRoot[] = "ash-constrain-pointer-to-root";
 
   return base::SysInfo::IsRunningOnChromeOS() ||
          base::CommandLine::ForCurrentProcess()->HasSwitch(
              kAshConstrainPointerToRoot);
 }
 
 bool DockedWindowsEnabled() {
   return base::CommandLine::ForCurrentProcess()->HasSwitch(
       ash::switches::kAshEnableDockedWindows);
 }
 
 }  // namespace switches
 }  // namespace ash