anchor.diff:     * @param overrides the overrides to be applied
      */
     void applyOverrides(Map<VariableElement, DartType> overrides) {
  -    overrides.forEach((VariableElement element, DartType type) {
  -      _overridenTypes[element] = type;
  -    });
  +    _overridenTypes.addAll(overrides);
     }
   
     /**
  
positive.code:           HashMap<String, Element> exportedNames =
                _createExportMapping(exportedLibrary, visitedElements);
            exportedNames = _applyCombinators(exportedNames, element.combinators);
            _addAllFromMap(definedNames, exportedNames);
          }
        }
        _addAllFromNamespace(definedNames,
  
negative.code:    * @param definedNames the mapping table to which the names in the given namespace are to be added
     * @param namespace the namespace containing the names to be added to this namespace
     */
    void _addAllFromNamespace(
        Map<String, Element> definedNames, Namespace namespace) {
      if (namespace != null) {
        definedNames.addAll(namespace.definedNames);
      }
    }
  
  