Write mojom and EnumTraits for display::HDCPState.

ui/display/mojo/display_constants_struct_traits.h

 // Copyright 2017 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.
 
 #ifndef UI_DISPLAY_MOJO_DISPLAY_CONSTANTS_STRUCT_TRAITS_H_
 #define UI_DISPLAY_MOJO_DISPLAY_CONSTANTS_STRUCT_TRAITS_H_
 
 #include "ui/display/mojo/display_constants.mojom.h"
 #include "ui/display/types/display_constants.h"
 
 namespace mojo {
 
 template <>
 struct EnumTraits<display::mojom::DisplayConnectionType,
                   display::DisplayConnectionType> {
   static display::mojom::DisplayConnectionType ToMojom(
       display::DisplayConnectionType type);
   static bool FromMojom(display::mojom::DisplayConnectionType type,
                         display::DisplayConnectionType* out);
 };
 
+template <>
+struct EnumTraits<display::mojom::HDCPState, display::HDCPState> {
+  static display::mojom::HDCPState ToMojom(display::HDCPState type);
+  static bool FromMojom(display::mojom::HDCPState type,
+                        display::HDCPState* out);
+};
+
 };  // namespace mojo
 
 #endif  // UI_DISPLAY_MOJO_DISPLAY_CONSTANTS_STRUCT_TRAITS_H_