Hmm, seems old to me, I remember having seen this on the ML weeks ago.
Phoronix: Wayland's Weston With Bubble-Style Notifications
For those using Wayland's Weston compositor with the stock shell, a patch was proposed today for implementing "bubbles list" style notifications...
http://www.phoronix.com/vr.php?view=MTMyNzk
Hmm, seems old to me, I remember having seen this on the ML weeks ago.
This does not sound like anything that belongs in the compositor.
Shouldn't this be a third-party service running inside Weston?