Remaining private libs

sdk/lib/core/sink.dart

 // Copyright (c) 2014, 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 "core.dart";
+part of "dart:core";
 
 /**
  * A generic destination for data.
  *
  * Multiple data values can be put into a sink, and when no more data is
  * available, the sink should be closed.
  *
  * This is a generic interface that other data receivers can implement.
  */
 abstract class Sink<T> {
   /**
    * Adds [data] to the sink.
    *
    * Must not be called after a call to [close].
    */
   void add(T data);
 
   /**
    * Closes the sink.
    *
    * The [add] method must not be called after this method.
    *
    * Calling this method more than once is allowed, but does nothing.
    */
   void close();
 }