[net/dns] Resolve AF_UNSPEC on dual-stacked systems. Sort addresses according to RFC3484.

net/dns/dns_response.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/dns/dns_response.h"
 
 #include "base/string_util.h"
 #include "base/sys_byteorder.h"
 #include "net/base/address_list.h"
 #include "net/base/big_endian.h"
@@ skipping 262 matching lines @@
       } else {
         if (addr_ttl_sec != record.ttl)
           return DNS_ADDRESS_TTL_MISMATCH;
       }
       ip_addresses.push_back(IPAddressNumber(record.rdata.begin(),
                                              record.rdata.end()));
     }
   }
 
   // TODO(szym): Extract TTL for NODATA results. http://crbug.com/115051
-  if (ip_addresses.empty())
-    return DNS_NO_ADDRESSES;
 
   // getcanonname in eglibc returns the first owner name of an A or AAAA RR.
   // If the response passed all the checks so far, then |expected_name| is it.
   *addr_list = AddressList::CreateFromIPAddressList(ip_addresses,
                                                     expected_name);
   *ttl = base::TimeDelta::FromSeconds(std::min(cname_ttl_sec, addr_ttl_sec));
-  return DNS_SUCCESS;
+  return DNS_PARSE_OK;
 }
 
 }  // namespace net