Language tests updated to use const instead of final.

tests/language/named_argument_in_const_creation_test.dart

Index: tests/language/named_argument_in_const_creation_test.dart
diff --git a/tests/language/named_argument_in_const_creation_test.dart b/tests/language/named_argument_in_const_creation_test.dart
index cd53423365e6ffe8adab3ce70c36fd11724f17d3..c0d079e840a186eaec7464c7421471b6af824ec1 100644
--- a/tests/language/named_argument_in_const_creation_test.dart
+++ b/tests/language/named_argument_in_const_creation_test.dart
@@ -6,7 +6,7 @@ class A {
   final x;
   final y;
   const A(a, [b]) : x = a, y = b;
-  static final test = const A(1, b: 2);
+  static const test = const A(1, b: 2);
 }
 
 main() {