Fix NetLog thread safety issue

net/base/x509_certificate_net_log_param.h

 // Copyright (c) 2012 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 NET_BASE_X509_CERT_NET_LOG_PARAM_H_
 #define NET_BASE_X509_CERT_NET_LOG_PARAM_H_
 #pragma once
 
 #include "net/base/net_log.h"
 
 namespace net {
 
 class X509Certificate;
 
-// Creates NetLog parameter to describe an X509Certificate.
-base::Value* NetLogX509CertificateCallback(
-    const X509Certificate* certificate,
-    NetLog::LogLevel log_level);
+// Creates a NetLog callback that returns a Value describing an X509Certificate.
+// The callback holds on to a reference to the certificate, which must not be
+// modified until the callback is destroyed.
+NetLog::ParametersCallback CreateNetLogX509CertificateCallback(
+    scoped_refptr<const X509Certificate> certificate);

[Ryan Sleevi, 2012/06/12 20:22:09]

const scoped_refptr<>&

Only scoped_ptr<>'s should be treated as movable - this avoids an extra
AddRef/Release on a temporary for the copy-by-value.

 
 }  // namespace net
 
 #endif  // NET_BASE_X509_CERT_NET_LOG_PARAM_H_