RFR: 8313424: JavaFX controls in the title bar [v52]

[Michael Strauß]

> Implementation of [`EXTENDED`](https://gist.github.com/mstr2/0befc541ee7297b6db2865cc5e4dbd09) and `EXTENDED_UTILITY` stage style.

Michael Strauß has updated the pull request with a new target base due to a merge or a rebase. The pull request now contains 67 commits:

 - Merge branch 'master' into feature/extended-window
 - remove HeaderButtonOverlay.allowRtl
 - minify button glyphs
 - typo
 - update copyright headers
 - Merge branch 'master' into feature/extended-window
 - Remove HeaderBarBase
 - Added HeaderBarBase.prefButtonHeight, removed Stage.initDefaultHeaderButtons
 - add "maximized" pseudo-class for custom maximize button
 - move StageTester to Tools menu
 - ... and 57 more: https://git.openjdk.org/jfx/compare/1c3cfcb8...e6e81001

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Changes: https://git.openjdk.org/jfx/pull/1605/files
  Webrev: https://webrevs.openjdk.org/?repo=jfx&pr=1605&range=51
  Stats: 6376 lines in 73 files changed: 5698 ins; 499 del; 179 mod
  Patch: https://git.openjdk.org/jfx/pull/1605.diff
  Fetch: git fetch https://git.openjdk.org/jfx.git pull/1605/head:pull/1605

PR: https://git.openjdk.org/jfx/pull/1605