/usr/lib/ is in ruby-coffee-rails 4.1.0-2.
This file is owned by root:root, with mode 0o755.
..
/usr/lib/ruby/
/usr/lib/ruby/vendor_ruby/
/usr/lib/ruby/vendor_ruby/rails/
/usr/lib/ruby/vendor_ruby/rails/generators/
/usr/lib/ruby/vendor_ruby/rails/generators/coffee/
/usr/lib/ruby/vendor_ruby/rails/generators/coffee/assets/
/usr/lib/ruby/vendor_ruby/rails/generators/coffee/assets/assets_generator.rb
/usr/lib/ruby/vendor_ruby/rails/generators/coffee/assets/templates/
/usr/lib/ruby/vendor_ruby/rails/generators/coffee/assets/templates/javascript.coffee
/usr/lib/ruby/vendor_ruby/coffee-rails.rb
/usr/lib/ruby/vendor_ruby/coffee/
/usr/lib/ruby/vendor_ruby/coffee/rails/
/usr/lib/ruby/vendor_ruby/coffee/rails/template_handler.rb
/usr/lib/ruby/vendor_ruby/coffee/rails/version.rb
/usr/lib/ruby/vendor_ruby/coffee/rails/engine.rb