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 FileTest {
   static Directory tempDirectory;
@@ skipping 449 matching lines @@
     Expect.equals(12, input.positionSync());
     input.readListSync(buffer, 12, 6);
     Expect.equals(18, input.positionSync());
     input.setPositionSync(8);
     Expect.equals(8, input.positionSync());
     input.closeSync();
   }
 
   static void testTruncate() {
     File file = new File(tempDirectory.path + "/out_truncate");
-    List buffer = const [65, 65, 65, 65, 65, 65, 65, 65, 65, 65];
+    // TODO(sgjesse): Handle this.

[Mads Ager (google), 2012/02/20 13:50:31]

Should be handled before commit as well.

[Søren Gjesse, 2012/02/22 16:27:07]

Done.

+    // List buffer = const [65, 65, 65, 65, 65, 65, 65, 65, 65, 65];
+    List buffer = new List(10);
+    for (int i = 0; i < 10; i++) {
+      buffer[i] = 65;
+    }
     file.errorHandler = (error) {
       Expect.fail("testTruncate: No errors expected");
     };
     file.openHandler = (RandomAccessFile openedFile) {
       openedFile.noPendingWriteHandler = () {
         openedFile.lengthHandler = (length) {
           Expect.equals(10, length);
           openedFile.truncateHandler = () {
             openedFile.lengthHandler = (length) {
               Expect.equals(5, length);
@@ skipping 344 matching lines @@
         testAppendSync();
         testWriteAppend();
         testOutputStreamWriteAppend();
       });
   }
 }
 
 main() {
   FileTest.testMain();
 }