Fix typo in stream.dart.

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 1475 matching lines @@
    * it may consume all the errors and only stop at a done event,
    * or it may be canceled early if the receiver don't want any further events.
    *
    * If the consumer stops listening because of some error preventing it
    * from continuing, it may report this error in the returned future,
    * otherwise it will just complete the future with `null`.
    */
   Future addStream(Stream<S> stream);
 
   /**
-   * Tells the consumer that no futher streams will be added.
+   * Tells the consumer that no further streams will be added.
    *
    * This allows the consumer to complete any remaining work and release
    * resources that are no longer needed
    *
    * Returns a future which is completed when the consumer has shut down.
    * If cleaning up can fail, the error may be reported in the returned future,
    * otherwise it completes with `null`.
    */
   Future close();
 }
@@ skipping 13 matching lines @@
  * be delayed until the underlying system has consumed the data added by the
  * [EventSink] methods.
  *
  * When [EventSink] methods are used, the [done] [Future] can be used to
  * catch any errors.
  *
  * When [close] is called, it will return the [done] [Future].
  */
 abstract class StreamSink<S> implements EventSink<S>, StreamConsumer<S> {
   /**
-   * Tells the stream sink that no futher streams will be added.
+   * Tells the stream sink that no further streams will be added.
    *
    * This allows the stream sink to complete any remaining work and release
    * resources that are no longer needed
    *
    * Returns a future which is completed when the stream sink has shut down.
    * If cleaning up can fail, the error may be reported in the returned future,
    * otherwise it completes with `null`.
    *
    * Returns the same future as [done].
    *
@@ skipping 202 matching lines @@
 class _ControllerEventSinkWrapper<T> implements EventSink<T> {
   EventSink _sink;
   _ControllerEventSinkWrapper(this._sink);
 
   void add(T data) { _sink.add(data); }
   void addError(error, [StackTrace stackTrace]) {
     _sink.addError(error, stackTrace);
   }
   void close() { _sink.close(); }
 }