onPanning event is not fired when panning is caused by velocity and not the user directly

[ZayneLu]

Describe the bug
The onPanning event is not fired when panning is caused by the velocity animation after the user release the mouse click.

To Reproduce
See this CodePen, and monitor the browser console; the event is fired when panning with the mouse, but once the mouse is released, the event is not fired, even though panning is still occurring.

Expected behavior
The onPanning event should be fired any time panning occurs, including when panning is occurring due to velocity.

Desktop (please complete the following information):

• OS: Windows 10
• The issue does not appear to be browser specific; the behavior is the same in Chrome, Vivaldi, and Firefox.