Change new List(n) to return fixed length list.

tests/lib/async/slow_consumer_test.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.
 
 // VMOptions=--old_gen_heap_size=64
 
 library slow_consumer_test;
 
 import 'dart:async';
 import 'dart:isolate';
@@ skipping 59 matching lines @@
     if (sentCount == targetCount) {
       controller.close();
       return;
     }
     int listSize = chunkSize;
     sentCount += listSize;
     if (sentCount > targetCount) {
       listSize -= sentCount - targetCount;
       sentCount = targetCount;
     }
-    controller.add(new List.fixedLength(listSize));
+    controller.add(new List(listSize));
     int ms = listSize * 1000 ~/ bytesPerSecond;
     Duration duration = new Duration(milliseconds: ms);
     if (!controller.isPaused) {
       pendingSend = new Timer(duration, send);
     }
   }
 
   onPauseStateChange() {
     // We don't care if we just unpaused or paused. In either case we just
     // call send which will test it for us.
@@ skipping 11 matching lines @@
   // file). If the consumer doesn't pause the data-provider it will run out of
   // heap-space.
 
   new DataProvider(800 * MB, 100 * MB, 1 * MB).stream
     .pipe(new SlowConsumer(200 * MB))
     .then((count) {
       port.close();
       Expect.equals(100 * MB, count);
     });
 }