dart2js: run dartfmt on tests

tests/compiler/dart2js/map_tracer_const_test.dart

 // Copyright (c) 2014, 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:expect/expect.dart';
 import "package:async_helper/async_helper.dart";
 
 import 'compiler_helper.dart';
 import 'type_mask_test_helper.dart';
 
@@ skipping 12 matching lines @@
 
 main() {
   var a = new A();
   a.map['fun'](3.3);
   print(closure(22));
 }
 ''';
 
 void main() {
   Uri uri = new Uri(scheme: 'source');
-  var compiler = compilerFor(TEST, uri,
-      expectedErrors: 0, expectedWarnings: 0);
+  var compiler = compilerFor(TEST, uri, expectedErrors: 0, expectedWarnings: 0);
   compiler.stopAfterTypeInference = true;
   asyncTest(() => compiler.run(uri).then((_) {
-    var commonMasks = compiler.commonMasks;
-    var typesInferrer = compiler.globalInference.typesInferrer;
-    var element = findElement(compiler, 'closure');
-    var mask = typesInferrer.getReturnTypeOfElement(element);
-    Expect.equals(commonMasks.numType, simplify(mask, compiler));
-  }));
+        var commonMasks = compiler.commonMasks;
+        var typesInferrer = compiler.globalInference.typesInferrer;
+        var element = findElement(compiler, 'closure');
+        var mask = typesInferrer.getReturnTypeOfElement(element);
+        Expect.equals(commonMasks.numType, simplify(mask, compiler));
+      }));
 }