anchor.diff:    final InternalAnalysisContext context;
     final SummaryDataStore _dataStore;
   
  -  _FileBasedSummaryResynthesizer _resynthesizer;
  +  StoreBasedSummaryResynthesizer _resynthesizer;
   
     ResynthesizerResultProvider(this.context, this._dataStore);
   
  
positive.code:    * Subclasses must call this method in their constructors.
     */
    void createResynthesizer() {
      _resynthesizer = new _FileBasedSummaryResynthesizer(context,
          context.sourceFactory, context.analysisOptions.strongMode, _dataStore);
    }
  
  
negative.code:    * every bundle that would be required to provide results for the [source].
     */
    bool hasResultsForSource(Source source);
  }
  
  /**
   * A concrete resynthesizer that serves summaries from [SummaryDataStore].
   */
  class StoreBasedSummaryResynthesizer extends SummaryResynthesizer {
    final SummaryDataStore _dataStore;
  
    StoreBasedSummaryResynthesizer(AnalysisContext context,
        SourceFactory sourceFactory, bool strongMode, this._dataStore)
        : super(context, sourceFactory, strongMode);
  
    @override
    LinkedLibrary getLinkedSummary(String uri) {
      return _dataStore.linkedMap[uri];
    }
  
    @override
    UnlinkedUnit getUnlinkedSummary(String uri) {
      return _dataStore.unlinkedMap[uri];
    }
  
    @override
    bool hasLibrarySummary(String uri) {
      LinkedLibrary linkedLibrary = _dataStore.linkedMap[uri];
      return linkedLibrary != null;
    }
  }
  
  /**
  