rails/rails — pull request #9997 by vipulnsward (2013-03-29 15:36:01+00:00)
Title: change merge to merge!

Change `merge` to `merge!` for performance gain[1]

in `HashWithIndifferentAccess#.[]`

[1] https://gist.github.com/vipulnsward/fa70dec670187713bfd8