Re-land "Format all multitests"

tests/language/sync_generator3_test.dart

 // Copyright (c) 2015, 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.
 
 // Test program for sync* generator functions and yielding in try blocks.
 
 import "package:expect/expect.dart";
 
 f() sync* {
   try {
@@ skipping 27 matching lines @@
   Expect.isTrue(i.moveNext());
   Expect.equals("a", i.current);
   Expect.isTrue(i.moveNext());
   Expect.equals("b", i.current);
   Expect.throws(() => i.moveNext(), (error) => error == "pow!");
 }
 
 main() {
   test1(); // //# test1: ok
   test2(); // //# test2: ok
-}
+}