Change hasSubscribers to hasListener.

utils/pub/error_group.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 error_group;
 
 import 'dart:async';
 
 import 'utils.dart';
 
@@ skipping 212 matching lines @@
   var _isDone = false;
 
   /// The underlying [StreamController] for [this].
   final StreamController _controller;
 
   /// The [StreamSubscription] that connects the wrapped [Stream] to
   /// [_controller].
   StreamSubscription _subscription;
 
   /// Whether [this] has any listeners.
-  bool get _hasListeners => _controller.hasSubscribers;
+  bool get _hasListeners => _controller.hasListener;
 
   /// Creates a new [_ErrorGroupFuture] that's a child of [_group] and wraps
   /// [inner].
   _ErrorGroupStream(this._group, Stream inner)
     : _controller = inner.isBroadcast ?
           new StreamController.broadcast() :
           new StreamController() {
     _subscription = inner.listen((v) {
       _controller.add(v);
     }, onError: (e) {
@@ skipping 19 matching lines @@
   void _signalError(AsyncError e) {
     if (_isDone) return;
     _subscription.cancel();
     // Call these asynchronously to work around issue 7913.
     new Future.immediate(null).then((_) {
       _controller.addError(e.error, e.stackTrace);
       _controller.close();
     });
   }
 }