Get rid of all the library tags.

lib/error_code.dart

 // Copyright (c) 2014, 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.
 
 /// Error codes defined in the [JSON-RPC 2.0 specificiation][spec].
 ///
 /// These codes are generally used for protocol-level communication. Most of
 /// them shouldn't be used by the application. Those that should have
 /// convenience constructors in [RpcException].
 ///
 /// [spec]: http://www.jsonrpc.org/specification#error_object
-library json_rpc_2.error_code;
-
 /// An error code indicating that invalid JSON was received by the server.
 const PARSE_ERROR = -32700;
 
 /// An error code indicating that the request JSON was invalid according to the
 /// JSON-RPC 2.0 spec.
 const INVALID_REQUEST = -32600;
 
 /// An error code indicating that the requested method does not exist or is
 /// unavailable.
 const METHOD_NOT_FOUND = -32601;
@@ skipping 18 matching lines @@
 String name(int errorCode) {
   switch (errorCode) {
     case PARSE_ERROR: return "parse error";
     case INVALID_REQUEST: return "invalid request";
     case METHOD_NOT_FOUND: return "method not found";
     case INVALID_PARAMS: return "invalid parameters";
     case INTERNAL_ERROR: return "internal error";
     default: return null;
   }
 }