anchor.diff: -import 'dart:collection';
  -
   import 'entities/entity_mapping.dart';
   import 'nodes/attribute.dart';
   import 'nodes/cdata.dart';
  
positive.code:     _stack.clear();
      final node = NodeBuilder();
      node.namespaces[ns.xmlUri] = NamespaceData.xmlData;
      _stack.addLast(node);
    }
  
    // Internal method to build a name.
  
negative.code:   final bool optimizeNamespaces;
  
    /// The current node stack of this builder.
    final List<NodeBuilder> _stack = [];
  
    /// Adds a [XmlText] node with the provided [text].
    ///
  