anchor.diff:    final DeclaredVariables declaredVariables = new DeclaredVariables();
   
     /**
  -   * If `true`, then analysis should be done without using tasks model.
  -   */
  -  final bool analyzeWithoutTasks;
  -
  -  /**
      * Information about the context root being analyzed by this driver.
      */
     final ContextRoot contextRoot;
  
positive.code:       this.contextRoot,
        SourceFactory sourceFactory,
        this._analysisOptions,
        {PackageBundle sdkBundle,
        this.analyzeWithoutTasks: true})
        : _logger = logger,
          _sourceFactory = sourceFactory.clone(),
          _sdkBundle = sdkBundle {
  
negative.code:       try {
          LibraryContext libraryContext = _createLibraryContext(library);
          try {
            LibraryAnalyzer analyzer = new LibraryAnalyzer(
                analysisOptions,
                declaredVariables,
                sourceFactory,
                _fileTracker.fsState,
                libraryContext.store,
                library);
            Map<FileState, UnitAnalysisResult> results = analyzer.analyze();
  
            List<int> bytes;
            CompilationUnit resolvedUnit;
            for (FileState unitFile in results.keys) {
              UnitAnalysisResult unitResult = results[unitFile];
              List<int> unitBytes =
                  _serializeResolvedUnit(unitResult.unit, unitResult.errors);
              String unitSignature = _getResolvedUnitSignature(library, unitFile);
              String unitKey = _getResolvedUnitKey(unitSignature);
              _byteStore.put(unitKey, unitBytes);
              if (unitFile == file) {
                bytes = unitBytes;
                resolvedUnit = unitResult.unit;
              }
            }
  
            // Return the result, full or partial.
  