Update SSL error handling code to account for Subject CN deprecation

net/cert/x509_certificate.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_CERT_X509_CERTIFICATE_H_
 #define NET_CERT_X509_CERTIFICATE_H_
 
 #include <stddef.h>
 #include <string.h>
 
@@ skipping 174 matching lines @@
   const CertPrincipal& issuer() const { return issuer_; }
 
   // Time period during which the certificate is valid.  More precisely, this
   // certificate is invalid before the |valid_start| date and invalid after
   // the |valid_expiry| date.
   // If we were unable to parse either date from the certificate (or if the cert
   // lacks either date), the date will be null (i.e., is_null() will be true).
   const base::Time& valid_start() const { return valid_start_; }
   const base::Time& valid_expiry() const { return valid_expiry_; }
 
-  // Gets the DNS names in the certificate.  Pursuant to RFC 2818, Section 3.1
+  // Gets the DNS names in the certificate. Pursuant to RFC 2818, Section 3.1
   // Server Identity, if the certificate has a subjectAltName extension of
   // type dNSName, this method gets the DNS names in that extension.
   // Otherwise, it gets the common name in the subject field.
+  //
+  // Note: Chrome has deprecated fallback to the subject field, see
+  // https://crbug.com/308330; prefer GetSubjectAltName() instead.
   void GetDNSNames(std::vector<std::string>* dns_names) const;
 
   // Gets the subjectAltName extension field from the certificate, if any.
   // For future extension; currently this only returns those name types that
   // are required for HTTP certificate name verification - see VerifyHostname.
   // Returns true if any dNSName or iPAddress SAN was present. If |dns_names|
   // is non-null, it will be set to all dNSNames present. If |ip_addrs| is
   // non-null, it will be set to all iPAddresses present.
   bool GetSubjectAltName(std::vector<std::string>* dns_names,
                          std::vector<std::string>* ip_addrs) const;
@@ skipping 242 matching lines @@
   // Untrusted intermediate certificates associated with this certificate
   // that may be needed for chain building.
   OSCertHandles intermediate_ca_certs_;
 
   DISALLOW_COPY_AND_ASSIGN(X509Certificate);
 };
 
 }  // namespace net
 
 #endif  // NET_CERT_X509_CERTIFICATE_H_