This CL will introduce a new way to do exponential back-off on failure within...

net/base/net_error_list.h

 // Copyright (c) 2010 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.
 
 // This file intentionally does not have header guards, it's included
 // inside a macro to generate enum.
 
 // This file contains the list of network errors.
 
 //
@@ skipping 150 matching lines @@
 // An SSL peer sent us a fatal bad_record_mac alert. This has been observed
 // from servers with buggy DEFLATE support.
 NET_ERROR(SSL_BAD_RECORD_MAC_ALERT, -126)
 
 // The proxy requested authentication (for tunnel establishment).
 NET_ERROR(PROXY_AUTH_REQUESTED, -127)
 
 // A known TLS strict server didn't offer the renegotiation extension.
 NET_ERROR(SSL_UNSAFE_NEGOTIATION, -128)
 
+// The request throttler module cancelled this request because the are too many
+// requests to a server that is failing requests.
+NET_ERROR(TEMPORARILY_THROTTLED_BY_DDOS, -129)
+
 // Certificate error codes
 //
 // The values of certificate error codes must be consecutive.
 
 // The server responded with a certificate whose common name did not match
 // the host name.  This could mean:
 //
 // 1. An attacker has redirected our traffic to his server and is
 //    presenting a certificate for which he knows the private key.
 //
@@ skipping 239 matching lines @@
 // Server rejected our command because we didn't issue the commands in right
 // order.
 // FTP response code 503.
 NET_ERROR(FTP_BAD_COMMAND_SEQUENCE, -607)
 
 // PKCS #12 import failed due to incorrect password.
 NET_ERROR(PKCS12_IMPORT_BAD_PASSWORD, -701)
 
 // PKCS #12 import failed due to other error.
 NET_ERROR(PKCS12_IMPORT_FAILED, -702)