Chromad: Add authentication flow

ash/public/interfaces/session_controller_traits.h

Index: ash/public/interfaces/session_controller_traits.h
diff --git a/ash/public/interfaces/session_controller_traits.h b/ash/public/interfaces/session_controller_traits.h
index 354c507748c44369a99be0f8bb0aa079bd8a1e62..25811888f387a7abb9390afe7e187a7c1b2d2bff 100644
--- a/ash/public/interfaces/session_controller_traits.h
+++ b/ash/public/interfaces/session_controller_traits.h
@@ -83,6 +83,8 @@ struct EnumTraits<ash::mojom::UserType, user_manager::UserType> {
         return ash::mojom::UserType::CHILD;
       case user_manager::USER_TYPE_ARC_KIOSK_APP:
         return ash::mojom::UserType::ARC_KIOSK;
+      case user_manager::USER_TYPE_AD:
+        return ash::mojom::UserType::AD;
       case user_manager::NUM_USER_TYPES:
         // Bail as this is not a valid user type.
         break;
@@ -115,6 +117,9 @@ struct EnumTraits<ash::mojom::UserType, user_manager::UserType> {
       case ash::mojom::UserType::ARC_KIOSK:
         *out = user_manager::USER_TYPE_ARC_KIOSK_APP;
         return true;
+      case ash::mojom::UserType::AD:
+        *out = user_manager::USER_TYPE_AD;
+        return true;
     }
     NOTREACHED();
     return false;