RFR: 8172095: Let Node.managed become CSS-styleable [v2]

[Abhinay Agarwal]

> 8172095: Let Node.managed become CSS-styleable

Abhinay Agarwal has updated the pull request incrementally with two additional commits since the last revision:

 - Add default value tests for setting / getting the managed property
 - Replace with HTML equivalent code

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Changes:
  - all: https://git.openjdk.java.net/jfx/pull/602/files
  - new: https://git.openjdk.java.net/jfx/pull/602/files/56b8f24b..394a47e3

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jfx&pr=602&range=01
 - incr: https://webrevs.openjdk.java.net/?repo=jfx&pr=602&range=00-01

  Stats: 29 lines in 2 files changed: 28 ins; 0 del; 1 mod
  Patch: https://git.openjdk.java.net/jfx/pull/602.diff
  Fetch: git fetch https://git.openjdk.java.net/jfx pull/602/head:pull/602

PR: https://git.openjdk.java.net/jfx/pull/602