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

sdk/lib/core/iterable.dart

Index: sdk/lib/core/iterable.dart
diff --git a/sdk/lib/core/iterable.dart b/sdk/lib/core/iterable.dart
index 2fe6c29281718e37b3bb28589318b6fdd7f9f05a..f5b6ba21480eaa461d2b4c376270c6305fd6f77a 100644
--- a/sdk/lib/core/iterable.dart
+++ b/sdk/lib/core/iterable.dart
@@ -156,7 +156,8 @@ abstract class Iterable<E> {
     return false;
   }
 
-  List<E> toList() => new List<E>.from(this);
+  List<E> toList({ bool growable: false }) =>
+      new List<E>.from(this, growable: growable);
   Set<E> toSet() => new Set<E>.from(this);
 
   /**