RFR: 8350917: Allow parent nodes to provide CSS styleable properties for child nodes

[John Hendrikx]

8350917: Allow parent nodes to provide CSS styleable properties for child nodes

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Commit messages:
 - Remove white space
 - Proof of concept parent provided styleable properties

Changes: https://git.openjdk.org/jfx/pull/1714/files
  Webrev: https://webrevs.openjdk.org/?repo=jfx&pr=1714&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8350917
  Stats: 579 lines in 6 files changed: 368 ins; 61 del; 150 mod
  Patch: https://git.openjdk.org/jfx/pull/1714.diff
  Fetch: git fetch https://git.openjdk.org/jfx.git pull/1714/head:pull/1714

PR: https://git.openjdk.org/jfx/pull/1714