one space before opening brace in class

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);
@@ skipping 530 matching lines @@
 
 /** A delayed event on a buffering stream subscription. */
 abstract class _DelayedEvent {
   /** Added as a linked list on the [StreamController]. */
   _DelayedEvent next;
   /** Execute the delayed event on the [StreamController]. */
   void perform(_EventDispatch dispatch);
 }
 
 /** A delayed data event. */
-class _DelayedData<T> extends _DelayedEvent{
+class _DelayedData<T> extends _DelayedEvent {
   final T value;
   _DelayedData(this.value);
   void perform(_EventDispatch<T> dispatch) {
     dispatch._sendData(value);
   }
 }
 
 /** A delayed error event. */
 class _DelayedError extends _DelayedEvent {
   final error;
@@ skipping 438 matching lines @@
       _FutureImpl<bool> hasNext = _futureOrPrefetch;
       _clear();
       hasNext._setValue(false);
       return;
     }
     _subscription.pause();
     _futureOrPrefetch = null;
     _state = _STATE_EXTRA_DONE;
   }
 }