dart2js: run dartfmt on tests

tests/compiler/dart2js/no_duplicate_stub_test.dart

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // 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.
 
 import "package:async_helper/async_helper.dart";
 import 'compiler_helper.dart';
 
 const String TEST = r"""
 class A {
   foo({a, b}) {}
@@ skipping 12 matching lines @@
   if (a is A) a.foo(a: 42);
 }
 
 baz(a) {
   if (a is B) a.foo(a: 42);
 }
 """;
 
 main() {
   asyncTest(() => compileAll(TEST).then((generated) {
-    RegExp regexp = new RegExp('foo\\\$1\\\$a: function');
-    Iterator<Match> matches = regexp.allMatches(generated).iterator;
-    checkNumberOfMatches(matches, 1);
-  }));
+        RegExp regexp = new RegExp('foo\\\$1\\\$a: function');
+        Iterator<Match> matches = regexp.allMatches(generated).iterator;
+        checkNumberOfMatches(matches, 1);
+      }));
 }