[jfx17u] Integrated: 8274929: Crash while reading specific clipboard content

[Kevin Rushforth]

Clean backport to `jfx17u`.

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Commit messages:
 - 8274929: Crash while reading specific clipboard content

Changes: https://git.openjdk.java.net/jfx17u/pull/20/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jfx17u&pr=20&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8274929
  Stats: 115 lines in 3 files changed: 111 ins; 0 del; 4 mod
  Patch: https://git.openjdk.java.net/jfx17u/pull/20.diff
  Fetch: git fetch https://git.openjdk.java.net/jfx17u pull/20/head:pull/20

PR: https://git.openjdk.java.net/jfx17u/pull/20