Fixes broken navigation introduced in [JDK-8370902](https://bugs.openjdk.org/browse/JDK-8370902) with non-zero paragraph spacing (above, below, line spacing).
Updated the Rich Editor Demo to allow setting paragraph line spacing in addition to space above/below (right click -> Paragraph). --------- - [x] I confirm that I make this contribution in accordance with the [OpenJDK Interim AI Policy](https://openjdk.org/legal/ai). ------------- Commit messages: - tabs and page up down - Merge branch 'master' into 8390913.down - whitespace - exhaustive test - using layout info - mid point - alternative solution - fix and test Changes: https://git.openjdk.org/jfx/pull/2280/files Webrev: https://webrevs.openjdk.org/?repo=jfx&pr=2280&range=00 Issue: https://bugs.openjdk.org/browse/JDK-8390913 Stats: 525 lines in 10 files changed: 339 ins; 91 del; 95 mod Patch: https://git.openjdk.org/jfx/pull/2280.diff Fetch: git fetch https://git.openjdk.org/jfx.git pull/2280/head:pull/2280 PR: https://git.openjdk.org/jfx/pull/2280
