Remove old #import, #source, and #library syntax from tests/standalone.

tests/standalone/io/http_auth_test.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.
 
-#import("dart:isolate");
-#import("dart:crypto");
-#import("dart:io");
-#import("dart:uri");
-#import("dart:utf");
+import "dart:isolate";
+import "dart:crypto";
+import "dart:io";
+import "dart:uri";
+import "dart:utf";
 
 class Server {
   HttpServer server;
   bool passwordChanged = false;
 
   Server() : server = new HttpServer();
 
   void start() {
     server.listen("127.0.0.1", 0);
     server.defaultRequestHandler =
@@ skipping 241 matching lines @@
 main() {
   testUrlUserInfo();
   testBasicNoCredentials();
   testBasicCredentials();
   testBasicAuthenticateCallback();
   // These teste are not normally run. They can be used for locally
   // testing with another web server (e.g. Apache).
   //testLocalServerBasic();
   //testLocalServerDigest();
 }