- Change "static final" to "static const" in the

utils/pub/yaml/model.dart

 // Copyright (c) 2012, 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.
 
 // This file contains the node classes for the internal representations of YAML
 // documents. These nodes are used for both the serialization tree and the
 // representation graph.
 
 /** A tag that indicates the type of a YAML node. */
 class _Tag implements Hashable {
   // TODO(nweiz): it would better match the semantics of the spec if there were
   // a singleton instance of this class for each tag.
 
-  static final SCALAR_KIND = 0;
-  static final SEQUENCE_KIND = 1;
-  static final MAPPING_KIND = 2;
+  static const SCALAR_KIND = 0;
+  static const SEQUENCE_KIND = 1;
+  static const MAPPING_KIND = 2;
 
-  static final String YAML_URI_PREFIX = 'tag:yaml.org,2002:';
+  static const String YAML_URI_PREFIX = 'tag:yaml.org,2002:';
 
   /** The name of the tag, either a URI or a local tag beginning with "!". */
   final String name;
 
   /** The kind of the tag: SCALAR_KIND, SEQUENCE_KIND, or MAPPING_KIND. */
   final int kind;
 
   _Tag(this.name, this.kind);
 
   _Tag.scalar(String name) : this(name, SCALAR_KIND);
@@ skipping 200 matching lines @@
   String toString() {
     var strContent = Strings.join(content.getKeys().
         map((k) => '${k}: ${content[k]}'), ', ');
     return '$tag {$strContent}';
   }
 
   int hashCode() => super.hashCode() ^ _hashCode(content);
 
   visit(_Visitor v) => v.visitMapping(this);
 }