Re-land "Format all multitests"

tests/language/check_method_override_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.
 
 class A {
   f([var x]) {}
   foo(var a, [x, y]) {}
 }
 
 class C extends A {
   f() {} //# 01: static type warning
   foo(var a, [x]) {} //# 02: static type warning
 }
 
 main() {
   new A().foo(2);
   new C().foo(1);
-}
+}