<AWT Dev> [9] Review request for 8166591 [macos 10.12] Trackpad scrolling of text on OS X 10.12 Sierra is very fast (Trackpad, Retina only)

[Sergey Malenkov]

> - The SCROLL_MASK_PHASE_CANCELLED  and SCROLL_MASK_PHASE_ENDED scroll masks
> are added.

Could you please use these masks in your fix?
Look at the following scenario:
- Perform slow and short scroll gesture
- Accumulator is less than threshold
- All wheel events during this gesture has wheelRotation=0
- Nothing is scrolled actually.
- Repeat several such gestures - nothing is scrolled

So I suggest to process the phase end to align accumulated value.
It adds an ability to scroll with short scroll gesture.
If you align accumulated value to bigger integer,
it also aligns scrolled lines automatically
when we support per-pixel scrolling.

-- 
Best regards,
Sergey A. Malenkov