Rename unsubscribe to cancel.

sdk/lib/io/stream_util.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.io;
 
 abstract class _BaseDataInputStream {
   int available();
 
   List<int> read([int len]) {
@@ skipping 201 matching lines @@
 
 
 class _InputStreamController extends StreamController<List<int>> {
   _InputStreamController(InputStream this._inputStream) {
     _inputStream.onClosed = close;
     _inputStream.onError = (error) => signalError(new AsyncError(error));
   }
 
   void onPauseStateChange() {
     if (isPaused) {
-      unlisten();
+      _unlisten();
     } else {
-      listen();
+      _listen();
     }
   }
 
   void onSubscriptionStateChange() {
-    if (hasSubscribers) listen();
+    if (hasSubscribers) _listen();
     // TODO(ajohnsen): Else destroy?
   }
 
-  void listen() {
+  void _listen() {
     _inputStream.onData = () {
       add(_inputStream.read());
     };
   }
 
-  void unlisten() {
+  void _unlisten() {
     _inputStream.onData = null;
   }
 
   InputStream _inputStream;
 }