rails/rails — pull request #12286 by i7an (2013-09-19 11:56:37+00:00)
Title: Add default_proc copying in HashWithIndifferentAccess

Add default_proc copying for `HashWithIndifferentAccess.new_from_hash_copying_default`, `HashWithIndifferentAccess#dup`, `HashWithIndifferentAccess#to_hash`