[jdk20u] RFR: 8305352: updateIconImages may lead to deadlock after JDK-8276849

[Dmitry Cherepanov]

Clean backport

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Commit messages:
 - Backport f968da97a5a5c68c28ad29d13fdfbe3a4adf5ef7

Changes: https://git.openjdk.org/jdk20u/pull/62/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk20u&pr=62&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8305352
  Stats: 3 lines in 1 file changed: 2 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jdk20u/pull/62.diff
  Fetch: git fetch https://git.openjdk.org/jdk20u.git pull/62/head:pull/62

PR: https://git.openjdk.org/jdk20u/pull/62