Update from https://crrev.com/304121

net/base/net_errors.cc

 // 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.
 
 #include "net/base/net_errors.h"
 
 #include "base/basictypes.h"
 #include "base/metrics/histogram.h"
 #include "base/strings/stringize_macros.h"
 
@@ skipping 38 matching lines @@
 
 bool IsCertificateError(int error) {
   // Certificate errors are negative integers from net::ERR_CERT_BEGIN
   // (inclusive) to net::ERR_CERT_END (exclusive) in *decreasing* order.
   // ERR_SSL_PINNED_KEY_NOT_IN_CERT_CHAIN is currently an exception to this
   // rule.
   return (error <= ERR_CERT_BEGIN && error > ERR_CERT_END) ||
          (error == ERR_SSL_PINNED_KEY_NOT_IN_CERT_CHAIN);
 }
 
+bool IsClientCertificateError(int error) {
+  switch (error) {
+    case ERR_BAD_SSL_CLIENT_AUTH_CERT:
+    case ERR_SSL_CLIENT_AUTH_PRIVATE_KEY_ACCESS_DENIED:
+    case ERR_SSL_CLIENT_AUTH_CERT_NO_PRIVATE_KEY:
+    case ERR_SSL_CLIENT_AUTH_SIGNATURE_FAILED:
+      return true;
+    default:
+      return false;
+  }
+}
+
 std::vector<int> GetAllErrorCodesForUma() {
   return base::CustomHistogram::ArrayToCustomRanges(
       kAllErrorCodes, arraysize(kAllErrorCodes));
 }
 
 Error FileErrorToNetError(base::File::Error file_error) {
   switch (file_error) {
     case base::File::FILE_OK:
       return net::OK;
     case base::File::FILE_ERROR_ACCESS_DENIED:
       return net::ERR_ACCESS_DENIED;
     case base::File::FILE_ERROR_INVALID_URL:
       return net::ERR_INVALID_URL;
     case base::File::FILE_ERROR_NOT_FOUND:
       return net::ERR_FILE_NOT_FOUND;
     default:
       return net::ERR_FAILED;
   }
 }
 
 }  // namespace net