Add IPAddress class as a replacement for the IPAddressNumber typedef.

net/base/ip_address_number.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_BASE_IP_ADDRESS_NUMBER_H_
 #define NET_BASE_IP_ADDRESS_NUMBER_H_
 
 #include <string>
 #include <vector>
 
 #include "base/basictypes.h"
 #include "base/strings/string_piece.h"
 #include "net/base/net_export.h"
 
 namespace net {
 
 // IPAddressNumber is used to represent an IP address's numeric value as an
 // array of bytes, from most significant to least significant. This is the
 // network byte ordering.
 //
 // IPv4 addresses will have length 4, whereas IPv6 address will have length 16.
+//
+// TODO(Martijnc): Remove the IPAddressNumber typedef. New code should use
+// IPAddress instead and existing code should be switched over.
+// https://crbug.com/496258
 typedef std::vector<unsigned char>
     IPAddressNumber;  // This is also duplicated in net_util.h
 typedef std::vector<IPAddressNumber> IPAddressList;
 
 static const size_t kIPv4AddressSize = 4;
 static const size_t kIPv6AddressSize = 16;
 
 // Returns true if an IP address hostname is in a range reserved by the IANA.
 // Works with both IPv4 and IPv6 addresses, and only compares against a given
 // protocols's reserved ranges.
@@ skipping 74 matching lines @@
 // Returns number of matching initial bits between the addresses |a1| and |a2|.
 unsigned CommonPrefixLength(const IPAddressNumber& a1,
                             const IPAddressNumber& a2);
 
 // Computes the number of leading 1-bits in |mask|.
 unsigned MaskPrefixLength(const IPAddressNumber& mask);
 
 }  // namespace net
 
 #endif  // NET_BASE_IP_ADDRESS_NUMBER_H_