RFR: 8313651: Add 'final' keyword to public property methods in controls [v4]

[Andy Goryachev]

> In the Control hierarchy, all property accessor methods must be declared `final`.
> 
> Added a test to check for missing `final` keyword and added the said keyword where required.

Andy Goryachev has updated the pull request incrementally with one additional commit since the last revision:

  review comments

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

Changes:
  - all: https://git.openjdk.org/jfx/pull/1213/files
  - new: https://git.openjdk.org/jfx/pull/1213/files/797285d8..505c8482

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jfx&pr=1213&range=03
 - incr: https://webrevs.openjdk.org/?repo=jfx&pr=1213&range=02-03

  Stats: 49 lines in 1 file changed: 9 ins; 24 del; 16 mod
  Patch: https://git.openjdk.org/jfx/pull/1213.diff
  Fetch: git fetch https://git.openjdk.org/jfx.git pull/1213/head:pull/1213

PR: https://git.openjdk.org/jfx/pull/1213