RFR: 8173321: Click on trough has no effect when cell height > viewport

[JoachimSchriek]

This is my (Joachim.Schriek at gmx.de) first contribution to openjfx. My Contributor Agreement is signed but still in review.
So please be patient with an absolute beginner as contributor ... .
The work of this pull request was fully done in my spare time.

I first filed the bug myself in 2017. I had begun working with JavaFX in 2014.

The two changes address the two problems mentioned in JDK-8173321:
- Using a JavaFX TableView, a click on the right trough has no effect when the cell height of the cell currently displayed is higher than viewport height
- The ScrollBar ist displayed with a minimal height.

The changes were tested and ran well with Java 17 and the current master branch of openjfx.

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Commit messages:
 - Replaces Tabs with Spaces
 - JDK-8173321: Click on trough has no effect when cell height > viewport

Changes: https://git.openjdk.org/jfx/pull/985/files
 Webrev: https://webrevs.openjdk.org/?repo=jfx&pr=985&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8173321
  Stats: 38 lines in 2 files changed: 19 ins; 7 del; 12 mod
  Patch: https://git.openjdk.org/jfx/pull/985.diff
  Fetch: git fetch https://git.openjdk.org/jfx pull/985/head:pull/985

PR: https://git.openjdk.org/jfx/pull/985