anchor.diff:    void buildClassExecutables(
         ClassElementImpl classElement, UnlinkedClass serializedClass) {
       ElementHolder memberHolder = new ElementHolder();
  -    fields = <String, FieldElementImpl>{};
       for (UnlinkedVariable serializedVariable in serializedClass.fields) {
  -      buildVariable(classElement, serializedVariable, memberHolder);
  +      buildField(classElement, serializedVariable, memberHolder);
       }
       bool constructorFound = false;
       constructors = <String, ConstructorElementImpl>{};
  
positive.code:       }
      }
      return variablesData;
    }
  
    /**
     * Resynthesize a [TopLevelVariableElement] or [FieldElement].
     */
    void buildVariable(
        ClassElementImpl enclosingClass, UnlinkedVariable serializedVariable,
        [ElementHolder holder]) {
      if (holder == null) {
        throw new UnimplementedError('Must be lazy');
      } else {
        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);
        fields[element.name] = element;
      }
    }
  
    /**
  
negative.code:     if (handle == null) {
        buildClassExecutables(classElement, serializedClass);
      }
      constructors = null;
      return classElement;
    }
  