Fix bugs in StreamController.addStream.

sdk/lib/async/broadcast_stream_controller.dart

Index: sdk/lib/async/broadcast_stream_controller.dart
diff --git a/sdk/lib/async/broadcast_stream_controller.dart b/sdk/lib/async/broadcast_stream_controller.dart
index 2e4366928a46f65e5938fa24fbe33093ee0ad64e..90c9761bfb38f2c5be051b782434784ad48573af 100644
--- a/sdk/lib/async/broadcast_stream_controller.dart
+++ b/sdk/lib/async/broadcast_stream_controller.dart
@@ -115,7 +115,7 @@ abstract class _BroadcastStreamController<T>
 
   Stream<T> get stream => new _BroadcastStream<T>(this);
 
-  StreamSink<T> get sink => new _StreamSinkWrapper<T>(this);
+  StreamControllerSink<T> get sink => new _StreamSinkWrapper<T>(this);
 
   bool get isClosed => (_state & _STATE_CLOSED) != 0;
 
@@ -238,10 +238,10 @@ abstract class _BroadcastStreamController<T>
 
   Future get done => _ensureDoneFuture();
 
-  Future addStream(Stream<T> stream) {
+  Future addStream(Stream<T> stream, {bool cancelOnError: true}) {
     if (!_mayAddEvent) throw _addEventError();
     _state |= _STATE_ADDSTREAM;
-    _addStreamState = new _AddStreamState(this, stream);
+    _addStreamState = new _AddStreamState(this, stream, cancelOnError);
     return _addStreamState.addStreamFuture;
   }