Re-land "Format all multitests"

tests/language_strong/mixin_invalid_inheritance2_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.
 
 class C<T> = Object with Malformed; // //# 01: compile-time error
 class C<T> = Object with T; // //# 02: compile-time error
 class C<T> = OBject with T<int>; // //# 03: compile-time error
 
 main() {
   new C<C>(); // //# 01: continued
   new C<C>(); // //# 02: continued
   new C<C>(); // //# 03: continued
-}
+}