dart2js: run dartfmt on tests

tests/compiler/dart2js_extra/21724_test.dart

Index: tests/compiler/dart2js_extra/21724_test.dart
diff --git a/tests/compiler/dart2js_extra/21724_test.dart b/tests/compiler/dart2js_extra/21724_test.dart
index a578ca69c55cab3f93bdd3d4300c86c294c1c6fc..eff9690b812b01f0dc3f190fe2bf3b649d6667b7 100644
--- a/tests/compiler/dart2js_extra/21724_test.dart
+++ b/tests/compiler/dart2js_extra/21724_test.dart
@@ -2,7 +2,6 @@
 // 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.
 
-
 // Regression test for issue 21724 - invalid call to local closure
 
 main() {
@@ -11,4 +10,3 @@ main() {
     foo();
   } catch (_) {}
 }
-