anchor.diff:  
     void addFilter(var filter) {
       if (filter is String) {
  -      // TODO person specifying multiple filters?
  -      // eg file:foo "bar"
         for (var parsed in Filter.parseAll(filter)) {
           addFilter(parsed);
         }
  
positive.code:   String _loggerName;
    String _messageExact;
    RegExp _messageRegex;
    String _rawMatcher;  // The actual text the person wrote.
    Level _minLevel;
    Level _exactLevel;
    String _fileName;
  
negative.code:   StreamSubscription<LogRecord> _sub;
  
    LogViewer.created() : super.created() {
      this.changes.listen((change) {
        if (_oldLog == log) {
          return;
  