Change the way hard splits are handled.

lib/src/rule/metadata.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.
 
 library dart_style.src.rule.metadata;
 
 import 'argument.dart';
 import 'rule.dart';
 
 /// Rule for handling splits between parameter metadata annotations and the
 /// following parameter.
 ///
 /// Metadata annotations for parameters (and type parameters) get some special
 /// handling. We use a single rule for all annotations in the parameter list.
 /// If any of the annotations split, they all do.
 ///
 /// Also, if the annotations split, we force the entire parameter list to fully
 /// split, both named and positional.
-class MetadataRule extends SimpleRule {
+class MetadataRule extends Rule {
   Rule _positionalRule;
   Rule _namedRule;
 
   /// Remembers that [rule] is the [PositionalRule] used by the argument list
   /// containing the parameter metadata using this rule.
   void bindPositionalRule(PositionalRule rule) {
     _positionalRule = rule;
   }
 
   /// Remembers that [rule] is the [NamedRule] used by the argument list
@@ skipping 27 matching lines @@
     super.forgetUnusedRules();
     if (_positionalRule != null && _positionalRule.index == null) {
       _positionalRule = null;
     }
 
     if (_namedRule != null && _namedRule.index == null) {
       _namedRule = null;
     }
   }
 }