RFR: 8335470: [XWayland] JavaFX tests that use AWT Robot fail on Wayland

[Alexander Zvegintsev]

This PR enables several previously disabled test cases for Wayland, as the required fixes are already in the promoted build. ([JDK-8335469](https://bugs.openjdk.org/browse/JDK-8335469), [JDK-8335468](https://bugs.openjdk.org/browse/JDK-8335468))

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Commit messages:
 - check JDK version
 - 8335470: [XWayland] JavaFX tests that use AWT Robot fail on Wayland

Changes: https://git.openjdk.org/jfx/pull/1661/files
  Webrev: https://webrevs.openjdk.org/?repo=jfx&pr=1661&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8335470
  Stats: 22 lines in 3 files changed: 13 ins; 8 del; 1 mod
  Patch: https://git.openjdk.org/jfx/pull/1661.diff
  Fetch: git fetch https://git.openjdk.org/jfx.git pull/1661/head:pull/1661

PR: https://git.openjdk.org/jfx/pull/1661