rails/rails — pull request #17420 by pwnall (2014-10-28 21:39:34+00:00)
Title: Fix guides snippet for registering a custom asset pipeline processor

For some reason, calling `register_engine` on `Sprockets` directly doesn't work. This version does.

I'm submitting this as a PR because I'm not sure if it's a bug, or if it's how things are supposed to be done.