Remove deprecated parts of dart:async.

sdk/lib/async/stream.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.
 
 part of dart.async;
 
 // -------------------------------------------------------------------
 // Core Stream types
 // -------------------------------------------------------------------
 
@@ skipping 384 matching lines @@
     bool first = true;
     subscription = this.listen(
       (T element) {
         if (!first) {
           buffer.write(separator);
         }
         first = false;
         try {
           buffer.write(element);
         } catch (e, s) {
-          _cancelAndError(subscription, result, _asyncError(e, s), s);
+          _cancelAndError(subscription, result, e, s);
         }
       },
       onError: (e) {
         result._completeError(e);
       },
       onDone: () {
         result._complete(buffer.toString());
       },
       cancelOnError: true);
     return result;
@@ skipping 807 matching lines @@
    *
    * If you need to stop listening for values before the stream iterator is
    * automatically closed, you must call [cancel] to ensure that the stream
    * is properly closed.
    *
    * Returns a future if the cancel-operation is not completed synchronously.
    * Otherwise returns `null`.
    */
   Future cancel();
 }