Remove some illegal enum forward declarations

sandbox/win/src/registry_policy.h

 // Copyright (c) 2006-2008 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 SANDBOX_SRC_REGISTRY_POLICY_H__
 #define SANDBOX_SRC_REGISTRY_POLICY_H__
 
 #include <stdint.h>
 
 #include <string>
 
 #include "base/strings/string16.h"
 #include "sandbox/win/src/crosscall_server.h"
 #include "sandbox/win/src/nt_internals.h"
 #include "sandbox/win/src/policy_low_level.h"
 #include "sandbox/win/src/sandbox_policy.h"
 
 namespace sandbox {
 
-enum EvalResult;
-
 // This class centralizes most of the knowledge related to registry policy
 class RegistryPolicy {
  public:
   // Creates the required low-level policy rules to evaluate a high-level
   // policy rule for registry IO, in particular open or create actions.
   static bool GenerateRules(const wchar_t* name,
                             TargetPolicy::Semantics semantics,
                             LowLevelPolicy* policy);
 
   // Performs the desired policy action on a create request with an
@@ skipping 18 matching lines @@
                             uint32_t attributes,
                             HANDLE root_directory,
                             uint32_t desired_access,
                             HANDLE* handle,
                             NTSTATUS* nt_status);
 };
 
 }  // namespace sandbox
 
 #endif  // SANDBOX_SRC_REGISTRY_POLICY_H__