dart2js: run dartfmt on tests

tests/compiler/dart2js_native/native_window1_frog_test.dart

Index: tests/compiler/dart2js_native/native_window1_frog_test.dart
diff --git a/tests/compiler/dart2js_native/native_window1_frog_test.dart b/tests/compiler/dart2js_native/native_window1_frog_test.dart
index b0588ec78323f23daa419db5c9b98ad4310aba45..80c56cb4ad82e1a43710dbd71fc01adf8465649b 100644
--- a/tests/compiler/dart2js_native/native_window1_frog_test.dart
+++ b/tests/compiler/dart2js_native/native_window1_frog_test.dart
@@ -16,13 +16,11 @@ class _DOMWindowJs implements Window {
   final int document;
 }
 
-class Win implements Window {
-}
+class Win implements Window {}
 
 main() {
   // By typing this variable to 'Window', Frog will optimize calls on
   // it.
   Window win = new Win();
-  Expect.throws(() => win.document,
-                (e) => e is NoSuchMethodError);
+  Expect.throws(() => win.document, (e) => e is NoSuchMethodError);
 }