/usr/lib/ruby/ is in libchronic-ruby 0.2.3-1.
This file is owned by root:root, with mode 0o755.
..
/usr/lib/ruby/1.8/
/usr/lib/ruby/1.8/chronic/
/usr/lib/ruby/1.8/chronic/chronic.rb
/usr/lib/ruby/1.8/chronic/grabber.rb
/usr/lib/ruby/1.8/chronic/handlers.rb
/usr/lib/ruby/1.8/chronic/ordinal.rb
/usr/lib/ruby/1.8/chronic/pointer.rb
/usr/lib/ruby/1.8/chronic/repeater.rb
/usr/lib/ruby/1.8/chronic/repeaters/
/usr/lib/ruby/1.8/chronic/repeaters/repeater_day.rb
/usr/lib/ruby/1.8/chronic/repeaters/repeater_day_name.rb
/usr/lib/ruby/1.8/chronic/repeaters/repeater_day_portion.rb
/usr/lib/ruby/1.8/chronic/repeaters/repeater_fortnight.rb
/usr/lib/ruby/1.8/chronic/repeaters/repeater_hour.rb
/usr/lib/ruby/1.8/chronic/repeaters/repeater_minute.rb
/usr/lib/ruby/1.8/chronic/repeaters/repeater_month.rb
/usr/lib/ruby/1.8/chronic/repeaters/repeater_month_name.rb
/usr/lib/ruby/1.8/chronic/repeaters/repeater_season.rb
/usr/lib/ruby/1.8/chronic/repeaters/repeater_season_name.rb
/usr/lib/ruby/1.8/chronic/repeaters/repeater_second.rb
/usr/lib/ruby/1.8/chronic/repeaters/repeater_time.rb
/usr/lib/ruby/1.8/chronic/repeaters/repeater_week.rb
/usr/lib/ruby/1.8/chronic/repeaters/repeater_weekend.rb
/usr/lib/ruby/1.8/chronic/repeaters/repeater_year.rb
/usr/lib/ruby/1.8/chronic/scalar.rb
/usr/lib/ruby/1.8/chronic/separator.rb
/usr/lib/ruby/1.8/chronic/time_zone.rb
/usr/lib/ruby/1.8/chronic.rb
/usr/lib/ruby/1.8/numerizer/
/usr/lib/ruby/1.8/numerizer/numerizer.rb