Add regression test for previously fixed bug.

lib/src/chunk_builder.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.
 
 library dart_style.src.chunk_builder;
 
 import 'chunk.dart';
 import 'dart_formatter.dart';
 import 'debug.dart' as debug;
 import 'line_writer.dart';
@@ skipping 493 matching lines @@
 
         if (chunk.isHardSplit && chunk.rule != ignoredSplit) {
           forceSplit = true;
           break;
         }
       }
     }
 
     // If there is a hard newline within the block, force the surrounding rule
     // for it so that we apply that constraint.
-    // TODO(rnystrom): This does the wrong thing when there is are multiple
-    // block arguments. We correctly force the rule, but then it gets popped
-    // off the writer's stack and it forgets it was forced. Can repro with:
-    //
-    // longFunctionName(
-    //     [longElementName, longElementName, longElementName],
-    //     [short]);
     if (forceSplit) _parent.forceRules();
 
     // Write the split for the block contents themselves.
     _parent._writeSplit(_parent._rules.last, _parent._blockArgumentNesting.last,
         flushLeft: _firstFlushLeft);
     return _parent;
   }
 
   /// Finishes writing and returns a [SourceCode] containing the final output
   /// and updated selection, if any.
@@ skipping 263 matching lines @@
     }
 
     // Harden every chunk that uses one of these rules.
     for (var chunk in _chunks) {
       if (hardenedRules.contains(chunk.rule)) {
         chunk.harden();
       }
     }
   }
 }