Add initial CertVerifyProcBuiltin.

net/cert/cert_verify_proc_builtin.h

+// Copyright (c) 2017 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_CERT_CERT_VERIFY_PROC_BUILTIN_H_
+#define NET_CERT_CERT_VERIFY_PROC_BUILTIN_H_
+
+#include "base/memory/ref_counted.h"
+#include "net/base/net_export.h"
+
+namespace net {
+
+class CertVerifyProc;
+
+// TODO(crbug.com/649017): This is not how other cert_verify_proc_*.h are
+// implemented -- they expose the type in the header. Use a consistent style
+// here too.
+NET_EXPORT scoped_refptr<CertVerifyProc> CreateCertVerifyProcBuiltin();
+
+}  // namespace net
+
+#endif  // NET_CERT_CERT_VERIFY_PROC_BUILTIN_H_