Migrate net/proxy/* to net::IPAddress.

net/base/ip_address.h

 // Copyright (c) 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.
 
 #ifndef NET_BASE_IP_ADDRESS_NET_H_
 #define NET_BASE_IP_ADDRESS_NET_H_
 
 #include <stddef.h>
 #include <stdint.h>
 
@@ skipping 131 matching lines @@
 // IP address whose |prefix_length_in_bits| most significant bits match
 // |ip_prefix| will be matched.
 //
 // In cases when an IPv4 address is being compared to an IPv6 address prefix
 // and vice versa, the IPv4 addresses will be converted to IPv4-mapped
 // (IPv6) addresses.
 NET_EXPORT bool IPAddressMatchesPrefix(const IPAddress& ip_address,
                                        const IPAddress& ip_prefix,
                                        size_t prefix_length_in_bits);
 
+// Parses an IP block specifier from CIDR notation to an
+// (IP address, prefix length) pair. Returns true on success and fills
+// |*ip_address| with the numeric value of the IP address and sets
+// |*prefix_length_in_bits| with the length of the prefix.
+//
+// CIDR notation literals can use either IPv4 or IPv6 literals. Some examples:
+//
+//    10.10.3.1/20
+//    a:b:c::/46
+//    ::1/128
+NET_EXPORT bool ParseCIDRBlock(const std::string& cidr_literal,
+                               IPAddress* ip_address,
+                               size_t* prefix_length_in_bits);
+
 // Returns number of matching initial bits between the addresses |a1| and |a2|.
 unsigned CommonPrefixLength(const IPAddress& a1, const IPAddress& a2);
 
 // Computes the number of leading 1-bits in |mask|.
 unsigned MaskPrefixLength(const IPAddress& mask);
 
 // Checks whether |address| starts with |prefix|. This provides similar
 // functionality as IPAddressMatchesPrefix() but doesn't perform automatic IPv4
 // to IPv4MappedIPv6 conversions and only checks against full bytes.
 template <size_t N>
 bool IPAddressStartsWith(const IPAddress& address, const uint8_t (&prefix)[N]) {
   if (address.size() < N)
     return false;
   return std::equal(prefix, prefix + N, address.bytes().begin());
 }
 
 }  // namespace net
 
 #endif  // NET_BASE_IP_ADDRESS_NET_H_