Stop using the Hashable interface.

runtime/bin/http_impl.dart

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 class _HttpHeaders implements HttpHeaders {
   _HttpHeaders() : _headers = new Map<String, List<String>>();
 
   List<String> operator[](String name) {
     name = name.toLowerCase();
     return _headers[name];
@@ skipping 1179 matching lines @@
   }
 
   void set onError(void callback(e)) {
     _requestOrResponse._streamSetErrorHandler(callback);
   }
 
   _HttpRequestResponseBase _requestOrResponse;
 }
 
 
-class _HttpConnectionBase implements Hashable {
+class _HttpConnectionBase {
   _HttpConnectionBase() : _sendBuffers = new Queue(),
                           _httpParser = new _HttpParser() {
     _hashCode = _nextHashCode;
     _nextHashCode = (_nextHashCode + 1) & 0xFFFFFFF;
   }
 
   void _connectionEstablished(Socket socket) {
     _socket = socket;
     // Register handler for socket events.
     _socket.onData = _onData;
@@ skipping 968 matching lines @@
 
 
 class _RedirectInfo implements RedirectInfo {
   const _RedirectInfo(int this.statusCode,
                       String this.method,
                       Uri this.location);
   final int statusCode;
   final String method;
   final Uri location;
 }