anchor.diff:    ConstructorElementImpl currentConstructor;
   
     /**
  -   * If a class is currently being resynthesized, map from field name to the
  -   * corresponding field element.  This is used when resynthesizing
  -   * initializing formal parameters.
  -   */
  -  Map<String, FieldElementImpl> fields;
  -
  -  /**
      * If a class is currently being resynthesized, map from constructor name to
      * the corresponding constructor element.  This is used when resynthesizing
      * constructor initializers.
  
positive.code:   void buildClassExecutables(
        ClassElementImpl classElement, UnlinkedClass serializedClass) {
      ElementHolder memberHolder = new ElementHolder();
      fields = <String, FieldElementImpl>{};
      for (UnlinkedVariable serializedVariable in serializedClass.fields) {
        buildVariable(classElement, serializedVariable, memberHolder);
      }
      bool constructorFound = false;
      constructors = <String, ConstructorElementImpl>{};
  
negative.code:   }
  
    /**
     * Resynthesize a [FieldElement].
     */
    void buildField(ClassElementImpl enclosingClass,
        UnlinkedVariable serializedVariable, ElementHolder holder) {
      FieldElementImpl element;
      if (serializedVariable.initializer?.bodyExpr != null &&
          (serializedVariable.isConst ||
              serializedVariable.isFinal && !serializedVariable.isStatic)) {
        element = new ConstFieldElementImpl.forSerialized(
            serializedVariable, enclosingClass);
      } else {
        element = new FieldElementImpl.forSerialized(
            serializedVariable, enclosingClass);
      }
      element.static = serializedVariable.isStatic;
      holder.addField(element);
      buildImplicitAccessors(element, holder);
    }
  
    /**
     * Build the implicit getter and setter associated with [element], and place
     * them in [holder].
     */
  