Create stubs for system certificate validation.

net/base/cert_verify_proc_mac.h

Index: net/base/cert_verify_proc_mac.h
diff --git a/net/base/cert_verify_proc_mac.h b/net/base/cert_verify_proc_mac.h
new file mode 100644
index 0000000000000000000000000000000000000000..8e28a6b1f9f9de4062bb96e55e7b52331e94000e
--- /dev/null
+++ b/net/base/cert_verify_proc_mac.h
@@ -0,0 +1,31 @@
+// 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_CERT_VERIFY_PROC_MAC_H_
+#define NET_BASE_CERT_VERIFY_PROC_MAC_H_
+
+#include "net/base/cert_verify_proc.h"
+
+namespace net {
+
+// Performs certificate path construction and validation using OS X's
+// Security.framework.
+class CertVerifyProcMac : public CertVerifyProc {
+ public:
+  CertVerifyProcMac();
+
+ protected:
+  virtual ~CertVerifyProcMac();
+
+ private:
+  virtual int VerifyInternal(X509Certificate* cert,
+                             const std::string& hostname,
+                             int flags,
+                             CRLSet* crl_set,
+                             CertVerifyResult* verify_result) OVERRIDE;
+};
+
+}  // namespace net
+
+#endif  // NET_BASE_CERT_VERIFY_PROC_MAC_H_