Fix a bunch of pub tests that started running "pub get".

test/barback/all_includes_all_default_directories_test.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.
 
 import 'package:scheduled_test/scheduled_test.dart';
 
 import '../descriptor.dart' as d;
 import '../serve/utils.dart';
 import '../test_pub.dart';
 
@@ skipping 31 matching lines @@
         d.dir('web', [
           d.file('file.txt', 'web')
         ]),
         // Only includes default source directories.
         d.nothing('unknown')
       ])
     ]).validate();
   });
 
   integration("serve --all finds assets in default source directories", () {
-    pubServe(args: ["--all"]);
+    pubServe(args: ["--all"], shouldGetFirst: true);
 
     requestShouldSucceed("file.txt", "benchmark", root: "benchmark");
     requestShouldSucceed("file.txt", "bin", root: "bin");
     requestShouldSucceed("file.txt", "example", root: "example");
     requestShouldSucceed("file.txt", "test", root: "test");
     requestShouldSucceed("file.txt", "web", root: "web");
 
     expectNotServed("unknown");
 
     endPubServe();
   });
 }