Use ByteArray's native for Socket and File.

runtime/bin/socket_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.
 
 
 class _SocketBase {
   // Bit flags used when communicating between the eventhandler and
   // dart code. The EVENT flags are used to indicate events of
   // interest when sending a message from dart code to the
   // eventhandler. When receiving a message from the eventhandler the
@@ skipping 291 matching lines @@
       }
       if (bytes < 0) {
         throw new IndexOutOfRangeException(bytes);
       }
       if ((offset + bytes) > buffer.length) {
         throw new IndexOutOfRangeException(offset + bytes);
       }
       // When using the Dart C API access to ObjectArray by index is
       // currently much faster. This function will make a copy of the
       // supplied List to an ObjectArray if it isn't already.
-      ObjectArray outBuffer;
+      List<int> outBuffer;

[cshapiro, 2012/01/27 23:00:04]

I think this can safely be retyped as a ByteArray even if the enclosing method
typed to return a List<int>, similar to how ObjectArray is used now.

[Anders Johnsen, 2012/01/27 23:42:39]

The thing is, that both a ByteArray and an ObjectArray can be assigned to
outBuffer, List<int> being the common ancestor. 

       int outOffset = offset;
       if (buffer is ObjectArray) {
         outBuffer = buffer;
+      } else if (buffer is ByteArray) {
+        outBuffer = buffer;
       } else {
-        outBuffer = new ObjectArray(bytes);
+        outBuffer = new ByteArray(bytes);
         outOffset = 0;
         int j = offset;
         for (int i = 0; i < bytes; i++) {
           outBuffer[i] = buffer[j];
           j++;
         }
       }
       var bytes_written = _writeList(outBuffer, outOffset, bytes);
       if (bytes_written < 0) {
         // If writing fails we return 0 as the number of bytes and
@@ skipping 127 matching lines @@
   bool _seenFirstOutEvent = false;
   bool _closedRead = false;
   bool _closedWrite = false;
   bool _pipe = false;
   Function _clientConnectHandler;
   Function _clientWriteHandler;
   SocketInputStream _inputStream;
   SocketOutputStream _outputStream;
 }