/usr/lib/ruby/vendor_ruby/actionmailer.rb is in ruby-actionmailer-2.3 2.3.14-3.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 | require 'action_mailer'
ActiveSupport::Deprecation.warn 'require "actionmailer" is deprecated and will be removed in Rails 3. Use require "action_mailer" instead.'
|