anchor.diff:        var duplicated = <DiagnosticName>[];
         for (var ignoredName in ignoredOnLine) {
           var name = ignoredName.name;
  -        if (unignorableNames.contains(name)) {
  +        if (_unignorableNames.contains(name)) {
             unignorable.add(ignoredName);
           } else if (namesIgnoredForFile.contains(name) ||
               !namedIgnoredOnLine.add(name)) {
  
positive.code:     var duplicated = <DiagnosticName>[];
      for (var ignoredName in ignoredForFile) {
        var name = ignoredName.name;
        if (unignorableNames.contains(name)) {
          unignorable.add(ignoredName);
        } else if (!namesIgnoredForFile.add(name)) {
          duplicated.add(ignoredName);
  
negative.code:   IgnoreValidator(this._errorReporter, this._reportedErrors, this._ignoreInfo,
        this._lineInfo) {
      var filePath = _errorReporter.source.fullName;
      _unignorableNames = _UnignorableNames.forFile(filePath);
    }
  
    /// Report any issues with ignore comments in the file being analyzed.
  