AsyncHostResolver: integrated HostCache, temporarily, until we have RR cache.

net/base/address_list.h

 // Copyright (c) 2011 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_ADDRESS_LIST_H_
 #define NET_BASE_ADDRESS_LIST_H_
 #pragma once
 
 #include <string>
 
@@ skipping 93 matching lines @@
   const struct addrinfo* head() const;
 
  private:
   struct Data;
 
   explicit AddressList(Data* data);
 
   scoped_refptr<Data> data_;
 };
 
+// Helper to create an AddressList that has a particular port. It has an
+// optimization to avoid allocating a new address linked list when the
+// port is already what we want.
+AddressList CreateAddressListUsingPort(const AddressList& src, int port);
+
 }  // namespace net
 
 #endif  // NET_BASE_ADDRESS_LIST_H_