Remove deprecated parts of dart:async.

sdk/lib/async/stream_impl.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.
 
 part of dart.async;
 
 /** Abstract and private interface for a place to put events. */
 abstract class _EventSink<T> {
   void _add(T data);
   void _addError(Object error, StackTrace stackTrace);
@@ skipping 511 matching lines @@
     // Send one event per call to moveNext.
     // If moveNext returns true, send the current element as data.
     // If moveNext returns false, send a done event and clear the _iterator.
     // If moveNext throws an error, send an error and clear the _iterator.
     // After an error, no further events will be sent.
     bool isDone;
     try {
       isDone = !_iterator.moveNext();
     } catch (e, s) {
       _iterator = null;
-      dispatch._sendError(_asyncError(e, s), s);
+      dispatch._sendError(e, s);
       return;
     }
     if (!isDone) {
       dispatch._sendData(_iterator.current);
     } else {
       _iterator = null;
       dispatch._sendDone();
     }
   }
 
@@ skipping 482 matching lines @@
       _Future<bool> hasNext = _futureOrPrefetch;
       _clear();
       hasNext._complete(false);
       return;
     }
     _subscription.pause();
     _futureOrPrefetch = null;
     _state = _STATE_EXTRA_DONE;
   }
 }