Change the way hard splits are handled.

lib/src/argument_list_visitor.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.argument_list_visitor;
 
 import 'package:analyzer/analyzer.dart';
 import 'package:analyzer/src/generated/scanner.dart';
 
 import 'chunk.dart';
@@ skipping 272 matching lines @@
 
     return new ArgumentSublist._(allArguments, positional, named, collections,
         leadingCollections, trailingCollections);
   }
 
   ArgumentSublist._(this._allArguments, this._positional, this._named,
       this._collections, this._leadingCollections, this._trailingCollections);
 
   void visit(SourceVisitor visitor) {
     if (_collections.isNotEmpty) {
-      _collectionRule = new SimpleRule(Cost.splitCollections);
+      _collectionRule = new Rule(Cost.splitCollections);
     }
 
     var rule = _visitPositional(visitor);
     _visitNamed(visitor, rule);
   }
 
   /// Writes the positional arguments, if any.
   PositionalRule _visitPositional(SourceVisitor visitor) {
     if (_positional.isEmpty) return null;
 
@@ skipping 118 matching lines @@
 
     // TODO(rnystrom): Should we step into parenthesized expressions?
 
     if (expression is ListLiteral) return expression.leftBracket;
     if (expression is MapLiteral) return expression.leftBracket;
 
     // Not a collection literal.
     return null;
   }
 }