Improve HTTPS error page text when SubjectAltName missing

components/ssl_errors/error_info.cc

 // Copyright 2015 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 "components/ssl_errors/error_info.h"
 
 #include <stddef.h>
 
 #include "base/i18n/message_formatter.h"
 #include "base/macros.h"
@@ skipping 20 matching lines @@
                                  const GURL& request_url) {
   base::string16 details, short_description;
   switch (error_type) {
     case CERT_COMMON_NAME_INVALID: {
       std::vector<std::string> dns_names;
       cert->GetSubjectAltName(&dns_names, nullptr);
 
       size_t i = 0;
       if (dns_names.empty()) {
         // The certificate had no DNS names, display an explanatory string.
-        // TODO(elawrence): Change the error messsage instead of just the
-        // placeholder string; see https://crbug.com/708268
-        dns_names.push_back("[missing_subjectAltName]");
+        details = l10n_util::GetStringFUTF16(
+            IDS_CERT_ERROR_NO_SUBJECT_ALTERNATIVE_NAMES_DETAILS,
+            UTF8ToUTF16(request_url.host()));
       } else {
         // If the certificate contains multiple DNS names, we choose the most
         // representative one -- either the DNS name that's also in the subject
         // field, or the first one. If this heuristic turns out to be
         // inadequate, we can consider choosing the DNS name that is the
         // "closest match" to the host name in the request URL, or listing all
         // the DNS names with an HTML <ul>.
         for (; i < dns_names.size(); ++i) {
           if (dns_names[i] == cert->subject().common_name)
             break;
         }
         if (i == dns_names.size())
           i = 0;
+
+        details = l10n_util::GetStringFUTF16(
+            IDS_CERT_ERROR_COMMON_NAME_INVALID_DETAILS,
+            UTF8ToUTF16(request_url.host()),
+            net::EscapeForHTML(UTF8ToUTF16(dns_names[i])));
       }
 
-      details = l10n_util::GetStringFUTF16(
-          IDS_CERT_ERROR_COMMON_NAME_INVALID_DETAILS,
-          UTF8ToUTF16(request_url.host()),
-          net::EscapeForHTML(UTF8ToUTF16(dns_names[i])));
       short_description = l10n_util::GetStringUTF16(
           IDS_CERT_ERROR_COMMON_NAME_INVALID_DESCRIPTION);
       break;
     }
     case CERT_DATE_INVALID:
       if (cert->HasExpired()) {
         // Make sure to round up to the smallest integer value not less than
         // the expiration value (https://crbug.com/476758).
         int expiration_value =
             (base::Time::Now() - cert->valid_expiry()).InDays() + 1;
@@ skipping 187 matching lines @@
 
   for (size_t i = 0; i < arraysize(kErrorFlags); ++i) {
     if ((cert_status & kErrorFlags[i]) && errors) {
       errors->push_back(
           ErrorInfo::CreateError(kErrorTypes[i], cert.get(), url));
     }
   }
 }
 
 }  // namespace ssl_errors