Convert pkg/http to use "package:" imports.

pkg/http/test/utils.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.
 
 library test_utils;
 
 import 'dart:io';
 import 'dart:json';
 import 'dart:uri';
 
-import '../../unittest/lib/unittest.dart';
-import '../lib/http.dart' as http;
-import '../lib/src/utils.dart';
+import 'package:unittest/unittest.dart';
+import 'package:http/http.dart' as http;
+import 'package:http/src/utils.dart';
 
 /// The current server instance.
 HttpServer _server;
 
 /// The URL for the current server instance.
 Uri get serverUrl => new Uri.fromString('http://localhost:${_server.port}');
 
 /// A dummy URL for constructing requests that won't be sent.
 Uri get dummyUrl => new Uri.fromString('http://dartlang.org/');
 
@@ skipping 141 matching lines @@
 const Matcher throwsRedirectLimitExceededException =
     const Throws(isRedirectLimitExceededException);
 
 class _RedirectLimitExceededException extends TypeMatcher {
   const _RedirectLimitExceededException() :
       super("RedirectLimitExceededException");
 
   bool matches(item, MatchState matchState) =>
     item is RedirectLimitExceededException;
 }