Rewrite Futures.

sdk/lib/async/stream_pipe.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;
 
 /**
  * Utility function to attach a stack trace to an [error]  if it doesn't have
  * one already.
  */
 _asyncError(Object error, Object stackTrace) {
   if (stackTrace == null) return error;
   if (getAttachedStackTrace(error) != null) return error;
   _attachStackTrace(error, stackTrace);
   return error;
 }
 
 /** Runs user code and takes actions depending on success or failure. */
 _runUserCode(userCode(), onSuccess(value), onError(error)) {
   try {
     onSuccess(userCode());
   } catch (e, s) {
     onError(_asyncError(e, s));
   }
 }
 
 /** Helper function to make an onError argument to [_runUserCode]. */
-_cancelAndError(StreamSubscription subscription, _FutureImpl future) =>
+_cancelAndError(StreamSubscription subscription, _Future future) =>
   (error) {
     subscription.cancel();
-    future._setError(error);
+    future._completeError(error);
   };
 
 
 /**
  * A [Stream] that forwards subscriptions to another stream.
  *
  * This stream implements [Stream], but forwards all subscriptions
  * to an underlying stream, and wraps the returned subscription to
  * modify the events on the way.
  *
@@ skipping 407 matching lines @@
 
   void handleError(error, EventSink<T> sink) {
     _handleError(error, sink);
   }
 
   void handleDone(EventSink<T> sink) {
     _handleDone(sink);
   }
 }