dart2js: run dartfmt on tests

tests/compiler/dart2js_native/native_exception2_test.dart

 // Copyright (c) 2013, 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.
 
 // Similar to native_exception_test.dart but also defines a native
 // class.  This exercises a different code path in emitter.dart.
 
 library native_exception2_test;
 
 import 'native_exception_test.dart' as other;
 import 'dart:_js_helper';
 
 @Native("NativeClass")
-class NativeClass {
-}
+class NativeClass {}
 
-makeNativeClass() native;
+makeNativeClass() native ;
 
 setup() native """
 function NativeClass() {}
 makeNativeClass = function() { return new NativeClass; }
 """;
 
 main() {
   setup();
   other.main();
 }