Port async file operations to be using native ports instead or an isolate

tests/standalone/src/FileTest.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.
 //
 // Dart test program for testing file I/O.
 
 #import("dart:io");
 
 class MyListOfOneElement implements List {
   int _value;
@@ skipping 405 matching lines @@
         openedFile.writeList(new MyListOfOneElement(2), 0, 1);
         var x = 12345678901234567890123456789012345678901234567890;
         var y = 12345678901234567890123456789012345678901234567893;
         openedFile.writeList([y - x], 0, 1);
         openedFile.writeList([260], 0, 1);  // 260 = 256 + 4 = 0x104.
         openedFile.writeList(const [261], 0, 1);
         openedFile.writeList(new MyListOfOneElement(262), 0, 1);
         x = 12345678901234567890123456789012345678901234567890;
         y = 12345678901234567890123456789012345678901234568153;
         openedFile.writeList([y - x], 0, 1);
-
+        openedFile.close();

[Mads Ager (google), 2012/02/23 08:57:44]

Why did you need to rewrite this test?

[Søren Gjesse, 2012/02/23 10:26:42]

Actually I didn't - reverted (I was testing calling close directly after write -
we should add some tests for that).

         openedFile.errorHandler = (s) {
           Expect.fail("No errors expected : $s");
         };
-        openedFile.noPendingWriteHandler = () {
-          openedFile.close();
-        };
         openedFile.closeHandler = () {
           // Check the written bytes.
           final File file2 = new File(fileName);
           var openedFile2 = file2.openSync();
           var length = openedFile2.lengthSync();
           Expect.equals(8, length);
           List data = new List(length);
           openedFile2.readListSync(data, 0, length);
           for (var i = 0; i < data.length; i++) {
             Expect.equals(i, data[i]);
@@ skipping 457 matching lines @@
         testWriteAppend();
         testOutputStreamWriteAppend();
         testWriteVariousLists();
       });
   }
 }
 
 main() {
   FileTest.testMain();
 }