anchor.diff:      declarationCasts = true;
       dart2jsHint = false;
       disableCacheFlushing = false;
  +    enabledExperiments = const <String>[];
       enabledPluginNames = const <String>[];
       enableLazyAssignmentOperators = false;
       enableTiming = false;
  
positive.code:     preserveComments = true;
      strongModeHints = false;
      trackCacheDependencies = true;
      useFastaParser = false;
    }
  
    @override
    void setCrossContextOptionsFrom(AnalysisOptions options) {
      enableLazyAssignmentOperators = options.enableLazyAssignmentOperators;
  
negative.code:       buffer.addBool(useFastaParser);
        buffer.addBool(isMixinSupportEnabled);
  
        // Append enabled experiments.
        buffer.addInt(enabledExperiments.length);
        for (String experimentName in enabledExperiments) {
          buffer.addString(experimentName);
        }
  
        // Append error processors.
        buffer.addInt(errorProcessors.length);
        for (ErrorProcessor processor in errorProcessors) {
  