View.EventHandler.handleDragStart is not working

Reproducible: always
Regression: No
Platform-specific: No
Steps to reproduce (Sample attached):
1. Create glass window with view
2. Attach window event that logs dragLeaveEvent
3. Try to drag something from window to any area outside window
Expected result: dragLeaveEvent invoked when mouse leaves window.
Actual result: dragLeaveEvent is not invoked at all.

That method lacks documentation so please comment if dragLeaveEvent support requires some additional code.