[jfx17u] RFR: 8273998: Clarify specification for Window properties controlled by the window manager

[Kevin Rushforth]

Clean backport to `jfx17u`.

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Commit messages:
 - 8273998: Clarify specification for Window properties controlled by the window manager

Changes: https://git.openjdk.java.net/jfx17u/pull/57/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jfx17u&pr=57&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8273998
  Stats: 84 lines in 2 files changed: 59 ins; 4 del; 21 mod
  Patch: https://git.openjdk.java.net/jfx17u/pull/57.diff
  Fetch: git fetch https://git.openjdk.java.net/jfx17u pull/57/head:pull/57

PR: https://git.openjdk.java.net/jfx17u/pull/57