Make Streams also cosider a thrown AsyncError a rethrow.

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;
 
 // States shared by single/multi stream implementations.
 
 /// Initial and default state where the stream can receive and send events.
 const int _STREAM_OPEN = 0;
@@ skipping 319 matching lines @@
 
   /**
    * Send a data event directly to each subscriber.
    */
   _sendData(T value) {
     assert(!_isPaused);
     assert(!_isComplete);
     _forEachSubscriber((subscriber) {
       try {
         subscriber._sendData(value);
+      } on AsyncError catch (e) {
+        e.throwDelayed();
       } catch (e, s) {
         new AsyncError(e, s).throwDelayed();
       }
     });
   }
 
   /**
    * Sends an error event directly to each subscriber.
    */
   void _sendError(AsyncError error) {
     assert(!_isPaused);
     assert(!_isComplete);
     _forEachSubscriber((subscriber) {
       try {
         subscriber._sendError(error);
+      } on AsyncError catch (e) {
+        e.throwDelayed();
       } catch (e, s) {
         new AsyncError.withCause(e, s, error).throwDelayed();
       }
     });
   }
 
   /**
    * Sends the "done" message directly to each subscriber.
    * This automatically stops further subscription and
    * unsubscribes all subscribers.
    */
   void _sendDone() {
     assert(!_isPaused);
     assert(_isClosed);
     _setComplete();
     if (!_hasSubscribers) return;
     _forEachSubscriber((subscriber) {
       _cancel(subscriber);
       try {
         subscriber._sendDone();
+      } on AsyncError catch (e) {
+        e.throwDelayed();
       } catch (e, s) {
         new AsyncError(e, s).throwDelayed();
       }
     });
     assert(!_hasSubscribers);
     _onSubscriptionStateChange();
   }
 }
 
 // -------------------------------------------------------------------
@@ skipping 695 matching lines @@
     if (_isComplete) {
       throw new StateError("Subscription has been canceled.");
     }
     if (_timer != null) {
       _timer.cancel();
       _timer = null;
     }
     _pauseCount = 0;
   }
 }