RFR: 8253597: TreeTableView: must select leaf row on click into indentation region [v2]

[Jeanette Winzenburg]

> .. but doesn't reliably (see report for details). Fixed in TreeTableCellBehavior to check for visibility of the
> disclosureNode.
> Added test that failed before and passes after, along with a couple of sanity tests.
> 
> Also added an alternative mouseEvent creation path into MouseEventFirer (and test) to work-around
> [JDK-8253769](https://bugs.openjdk.java.net/browse/JDK-8253769)

Jeanette Winzenburg has updated the pull request incrementally with one additional commit since the last revision:

  fixed typo

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

Changes:
  - all: https://git.openjdk.java.net/jfx/pull/313/files
  - new: https://git.openjdk.java.net/jfx/pull/313/files/0fe1ca48..d06812eb

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jfx&pr=313&range=01
 - incr: https://webrevs.openjdk.java.net/?repo=jfx&pr=313&range=00-01

  Stats: 1 line in 1 file changed: 0 ins; 0 del; 1 mod
  Patch: https://git.openjdk.java.net/jfx/pull/313.diff
  Fetch: git fetch https://git.openjdk.java.net/jfx pull/313/head:pull/313

PR: https://git.openjdk.java.net/jfx/pull/313