Format all tests.

tests/language/mixin_super_constructor_multiple_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.
 
 import "package:expect/expect.dart";
 
 class S {
   int i;
   S.foo() : i = 1742;
 }
 
-class M1 { }
+class M1 {}
 
-class M2 { }
+class M2 {}
 
 class C extends S with M1, M2 {
   C.foo() : super.foo();
 }
 
 main() {
   Expect.equals(1742, new C.foo().i);
 }