Use a forward declaration of RSAPrivateKey in crypto/signature_creator.h.

crypto/signature_creator_openssl.cc

 // Copyright (c) 2011 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 "crypto/signature_creator.h"
 
 #include <openssl/evp.h>
 
 #include "base/logging.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/stl_util.h"
 #include "crypto/openssl_util.h"
+#include "crypto/rsa_private_key.h"
 
 namespace crypto {
 
 // static
 SignatureCreator* SignatureCreator::Create(RSAPrivateKey* key) {
   OpenSSLErrStackTracer err_tracer(FROM_HERE);
   scoped_ptr<SignatureCreator> result(new SignatureCreator);
   result->key_ = key;
   if (!EVP_SignInit_ex(result->sign_context_, EVP_sha1(), NULL))
     return NULL;
@@ skipping 22 matching lines @@
   int rv = EVP_SignFinal(sign_context_, vector_as_array(signature), &len, key);
   if (!rv) {
     signature->clear();
     return false;
   }
   signature->resize(len);
   return true;
 }
 
 }  // namespace crypto