x509_certificate_model_openssl: implement ProcessRawBitsSignatureWrap

chrome/common/net/x509_certificate_model_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 "chrome/common/net/x509_certificate_model.h"
 
 #include <openssl/bio.h>
 #include <openssl/obj_mac.h>
 #include <openssl/sha.h>
 #include <openssl/x509v3.h>
@@ skipping 1200 matching lines @@
       return rv;
     }
     default:
       rv = ProcessRawAsn1String(X509_get_X509_PUBKEY(cert_handle)->public_key);
       return rv;
   }
 }
 
 std::string ProcessRawBitsSignatureWrap(
     net::X509Certificate::OSCertHandle cert_handle) {
-  // TODO(bulach): implement me.
-  return "";
+  return ProcessRawAsn1String(cert_handle->signature);
 }
 
 }  // namespace x509_certificate_model