Remove more libraries directives from server

pkg/analysis_server/lib/src/server/http_server.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.
 
-library analysis_server.src.server.http_server;
-
 import 'dart:async';
 import 'dart:io';
 
 import 'package:analysis_server/src/channel/web_socket_channel.dart';
 import 'package:analysis_server/src/socket_server.dart';
 import 'package:analysis_server/src/status/get_handler.dart';
 import 'package:analysis_server/src/status/get_handler2.dart';
 
 /**
  * Instances of the class [HttpServer] implement a simple HTTP server. The
@@ skipping 124 matching lines @@
    */
   void _returnUnknownRequest(HttpRequest request) {
     HttpResponse response = request.response;
     response.statusCode = HttpStatus.NOT_FOUND;
     response.headers.contentType =
         new ContentType("text", "plain", charset: "utf-8");
     response.write('Not found');
     response.close();
   }
 }