I updated one of my systems to OS X 10.10.3 today, and ran across this odd message in the system log:
NotificationCenter: Layout still needs update after calling -[NCScrollView layout]. NCScrollView or one of its superclasses may have overridden -layout without calling super. Or, something may have dirtied layout in the middle of updating it. Both are programming errors in Cocoa Autolayout. The former is pretty likely to arise if some pre-Cocoa Autolayout class had a method called layout, but it should be fixed.
I hope somebody at Apple is looking at their logs….