Fix DelegatingStreamChannel.

I apparently forgot to add imports and named it the wrong thing.

R=rnystrom@google.com

Review URL: https://codereview.chromium.org//1615043004 .

pkgs/stream_channel/lib/src/delegating_stream_channel.dart

diff --git a/pkgs/stream_channel/lib/src/delegating_stream_channel.dart b/pkgs/stream_channel/lib/src/delegating_stream_channel.dart
index 9d6ad90..4434cf6 100644
--- a/pkgs/stream_channel/lib/src/delegating_stream_channel.dart
+++ b/pkgs/stream_channel/lib/src/delegating_stream_channel.dart
@@ -2,16 +2,20 @@
 // 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.
 
+import 'dart:async';
+
+import '../stream_channel.dart';
+
 /// A simple delegating wrapper around [StreamChannel].
 ///
 /// Subclasses can override individual methods, or use this to expose only
 /// [StreamChannel] methods.
-class StreamChannelView<T> extends StreamChannelMixin<T> {
+class DelegatingStreamChannel<T> extends StreamChannelMixin<T> {
   /// The inner channel to which methods are forwarded.
   final StreamChannel<T> _inner;
 
   Stream<T> get stream => _inner.stream;
   StreamSink<T> get sink => _inner.sink;
 
-  StreamChannelView(this._inner);
+  DelegatingStreamChannel(this._inner);
 }