- Fix use of String operator + in runtime and standalone libraries.

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 _HttpRequestResponseBase {
   _HttpRequestResponseBase(_HttpConnectionBase this._httpConnection)
       : _contentLength = -1,
         _keepAlive = false,
         _headers = new Map();
 
@@ skipping 325 matching lines @@
       case HttpStatus.REQUESTED_RANGE_NOT_SATISFIABLE:
         return "Requested range not satisfiable";
       case HttpStatus.EXPECTATION_FAILED: return "Expectation Failed";
       case HttpStatus.INTERNAL_SERVER_ERROR: return "Internal Server Error";
       case HttpStatus.NOT_IMPLEMENTED: return "Not Implemented";
       case HttpStatus.BAD_GATEWAY: return "Bad Gateway";
       case HttpStatus.SERVICE_UNAVAILABLE: return "Service Unavailable";
       case HttpStatus.GATEWAY_TIMEOUT: return "Gateway Time-out";
       case HttpStatus.HTTP_VERSION_NOT_SUPPORTED:
         return "Http Version not supported";
-      default: return "Status " + statusCode.toString();
+      default: return "Status $statusCode";
     }
   }
 
   bool _writeHeader() {
     List<int> data;
     OutputStream stream = _httpConnection.outputStream;
 
     // Write status line.
     stream.write(_Const.HTTP11);
     _writeSP();
@@ skipping 781 matching lines @@
     _onError = callback;
   }
 
   Function _onOpen;
   Function _onError;
   Map<String, Queue<_SocketConnection>> _openSockets;
   Set<_SocketConnection> _activeSockets;
   Timer _evictionTimer;
   bool _shutdown;  // Has this HTTP client been shutdown?
 }