Rename blahHandler to onBlah throughout dart:io.

tests/standalone/src/ListOutputStreamTest.dart

-// Copyright (c) 2011, the Dart project authors.  Please see the AUTHORS file
+// 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.
 
 #import("dart:io");
 #import("dart:isolate");
 
 void testEmptyListOutputStream1() {
   OutputStream stream = new ListOutputStream();
   Expect.equals(null, stream.contents());
   stream.close();
   Expect.equals(null, stream.contents());
   Expect.throws(() { stream.write([0]); });
 }
 
 
 void testEmptyListOutputStream2() {
   OutputStream stream = new ListOutputStream();
   ReceivePort donePort = new ReceivePort();
 
   void onNoPendingWrite() {
     stream.close();
   }
 
   void onClose() {
     Expect.equals(null, stream.contents());
     donePort.toSendPort().send(null);
   }
 
-  stream.noPendingWriteHandler = onNoPendingWrite;
-  stream.closeHandler = onClose;
+  stream.onNoPendingWrite = onNoPendingWrite;
+  stream.onClose = onClose;
 
   donePort.receive((x,y) => donePort.close());
 }
 
 
 void testListOutputStream1() {
   OutputStream stream = new ListOutputStream();
   Expect.equals(null, stream.contents());
   stream.write([1, 2]);
   stream.writeFrom([1, 2, 3, 4, 5], 2, 2);
@@ skipping 30 matching lines @@
 
   void onClose() {
     Expect.equals(4, stage);
     var contents = stream.contents();
     Expect.equals(5, contents.length);
     for (var i = 0; i < contents.length; i++) Expect.equals(i + 1, contents[i]);
     Expect.equals(null, stream.contents());
     donePort.toSendPort().send(null);
   }
 
-  stream.noPendingWriteHandler = onNoPendingWrite;
-  stream.closeHandler = onClose;
+  stream.onNoPendingWrite = onNoPendingWrite;
+  stream.onClose = onClose;
 
   donePort.receive((x,y) => donePort.close());
 }
 
 main() {
   testEmptyListOutputStream1();
   testEmptyListOutputStream2();
   testListOutputStream1();
   testListOutputStream2();
 }