rails/rails — pull request #18119 by joker1007 (2014-12-21 12:07:16+00:00)
Title: Add 'require' for Hash#with_indifferent_access to active_job/arguments.rb

`ActiveJob::Arguments` uses Hash#with_indifferent_access.
But, activejob gem does not require Hash extension library.
When we use activejob as standalone,
we need extra require statement. This is unhandy.

This commit fixes it.