Revert "Remaining private libs"

sdk/lib/io/common.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";
+part of "io.dart";
 
 // Constants used when working with native ports.
 // These must match the constants in runtime/bin/dartutils.h class CObject.
 const int _SUCCESS_RESPONSE = 0;
 const int _ILLEGAL_ARGUMENT_RESPONSE = 1;
 const int _OSERROR_RESPONSE = 2;
 const int _FILE_CLOSED_RESPONSE = 3;
 
 const int _ERROR_RESPONSE_ERROR_TYPE = 0;
 const int _OSERROR_RESPONSE_ERROR_CODE = 1;
@@ skipping 94 matching lines @@
     }
     newBuffer[i] = value;
     j++;
   }
   return new _BufferAndStart(newBuffer, 0);
 }
 
 class _IOCrypto {
   external static Uint8List getRandomBytes(int count);
 }