RFR: 8321722: Tab header flickering when dragging slowly other tabs and reordering uncompleted

[Kevin Rushforth]

On Mon, 11 Dec 2023 18:36:35 GMT, Jose Pereda <jpereda at openjdk.org> wrote:

> This PR prevents changes in direction when dragging a tab header over a TabPane control, if delta value is zero, which can happen with slow drag events, in order to prevent starting and stopping too frequently the animation of the target tab header in opposite directions.

Marked as reviewed by kcr (Lead).

-------------

PR Review: https://git.openjdk.org/jfx/pull/1304#pullrequestreview-1776158565