anchor.diff:     * instance:
      *    logger.on.record.add((record) { ... });
      */
  -  LoggerEvents get on() => new LoggerEvents(this);
  +  LoggerEvents get on => new LoggerEvents(this);
   
     /** Adds a handler to listen whenever a log record is added to this logger. */
     void _addHandler(LoggerHandler handler) {
  
positive.code:   }
  
    /** Top-level root [Logger]. */
    static get root() => new Logger('');
  
    /** All [Logger]s in the system. */
    static Map<String, Logger> _loggers;
  
negative.code:   final String name;
  
    /** The full name of this logger, which includes the parent's full name. */
    String get fullName =>
        (parent == null || parent.name == '') ? name : '${parent.fullName}.$name';
  
    /** Parent of this logger in the hierarchy of loggers. */
  