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

tests/lib/async/slow_consumer3_test.dart

Index: tests/lib/async/slow_consumer3_test.dart
diff --git a/tests/lib/async/slow_consumer3_test.dart b/tests/lib/async/slow_consumer3_test.dart
index 24386add57f1f82fc4ac8512b2ebd8bcb4ab982a..7f3794bd5e8bad065f8e2f660168e9626ce85891 100644
--- a/tests/lib/async/slow_consumer3_test.dart
+++ b/tests/lib/async/slow_consumer3_test.dart
@@ -53,7 +53,7 @@ Stream<List> dataGenerator(int bytesTotal, int chunkSize) {
   int chunks = bytesTotal ~/ chunkSize;
   return new Stream.fromIterable(new Iterable.generate(chunks, (_) {
     // This assumes one byte per entry. In practice it will be more.
-    return new List<int>.fixedLength(chunkSize);
+    return new List<int>(chunkSize);
   }));
 }