Re-land "Format all multitests"

tests/language/string_interpolation_test.dart

 // Copyright (c) 2011, 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";
 
 // Tests for string interpolation
 class StringInterpolationTest {
-
   StringInterpolationTest() {}
 
   static void m() {}
 
   static const int i = 1;
   static const String a = "<hi>";
 
   int j;
   int k;
 
@@ skipping 54 matching lines @@
   }
 
   String embedMultipleFields() {
     return "j = ${j}; k = ${k}";
   }
 }
 
 main() {
   StringInterpolationTest.testMain(false);
 }