dart2js: run dartfmt on tests

tests/compiler/dart2js_extra/inference_nsm_mirrors_test.dart

Index: tests/compiler/dart2js_extra/inference_nsm_mirrors_test.dart
diff --git a/tests/compiler/dart2js_extra/inference_nsm_mirrors_test.dart b/tests/compiler/dart2js_extra/inference_nsm_mirrors_test.dart
index 46a97378d0e71b06fd3ba324dd2d29d76a95178e..424f7ca755996002ee32e40daafbfc989f9e22ed 100644
--- a/tests/compiler/dart2js_extra/inference_nsm_mirrors_test.dart
+++ b/tests/compiler/dart2js_extra/inference_nsm_mirrors_test.dart
@@ -24,6 +24,6 @@ main() {
   Expect.equals(42, new B().foo(0));
   // In checked mode we should get a type error. In unchecked mode it should be
   // an argument error.
-  Expect.throws(() => new A().foo('foo'),
-                (e) => e is ArgumentError || e is TypeError);
+  Expect.throws(
+      () => new A().foo('foo'), (e) => e is ArgumentError || e is TypeError);
 }