mozilla/metrics-graphics — pull request #239 by dandehavilland (2014-11-28 11:59:27+00:00)
Title: Added rollout_callback, inverse of rollover_callback

This is something I would find very useful as I'm displaying a custom rollover panel and would like to hide that on rollout.

If this is something you'd consider adding to the core, please let me know and I can add to the documentation.

(Also trimmed excess whitespace)