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

net/base/ip_address.h

Index: net/base/ip_address.h
diff --git a/net/base/ip_address.h b/net/base/ip_address.h
index f1f244e7fbf5877e06fa87b88d90d8a3107d9509..b9ad3b1e97f5e3007dc8e4bff154cda13aa2c22c 100644
--- a/net/base/ip_address.h
+++ b/net/base/ip_address.h
@@ -149,6 +149,10 @@ NET_EXPORT bool IPAddressMatchesPrefix(const IPAddress& ip_address,
                                        const IPAddress& ip_prefix,
                                        size_t prefix_length_in_bits);
 
+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);