Registered test waiter for ember-raf-scheduler
Registered test waiter for ember-raf-scheduler

no issue
- recommended as per `vertical-collection` docs: https://github.com/html-next/vertical-collection#testing
- ensures Ember's `wait` helper is aware of any raf-scheduler loops

kevinansfield/Ghost-Admin,TryGhost/Ghost-Admin,TryGhost/Ghost-Admin,kevinansfield/Ghost-Admin