Run pub tests against older versions of barback.

third_party/pkg/barback-0.13.0/lib/src/utils.dart

 // Copyright (c) 2013, 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 barback.utils;
 
 import 'dart:async';
 import 'dart:typed_data';
 
 import 'package:stack_trace/stack_trace.dart';
@@ skipping 290 matching lines @@
     subscription = callback().listen(controller.add,
         onError: controller.addError,
         onDone: controller.close);
   },
       onCancel: () => subscription.cancel(),
       onPause: () => subscription.pause(),
       onResume: () => subscription.resume(),
       sync: true);
   return controller.stream;
 }
-
-/// Creates a single-subscription stream from a broadcast stream.
-///
-/// The returned stream will enqueue events from [broadcast] until a listener is
-/// attached, then pipe events to that listener.
-Stream broadcastToSingleSubscription(Stream broadcast) {
-  if (!broadcast.isBroadcast) return broadcast;
-
-  // TODO(nweiz): Implement this using a transformer when issues 18588 and 18586
-  // are fixed.
-  var subscription;
-  var controller = new StreamController(onCancel: () => subscription.cancel());
-  subscription = broadcast.listen(controller.add,
-      onError: controller.addError,
-      onDone: controller.close);
-  return controller.stream;
-}