[jdk21u-dev] RFR: 8335131: Test "javax/swing/JColorChooser/Test6977726.java" failed on ubuntu x64 because "Preview" title is missing for GTK L&F

[Goetz Lindenmaier]

I backport this for parity with 21.0.9-oracle.

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Commit messages:
 - Backport 0c3720b42176c7bc92105be87df7449973fbcea0

Changes: https://git.openjdk.org/jdk21u-dev/pull/1993/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk21u-dev&pr=1993&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8335131
  Stats: 8 lines in 1 file changed: 7 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jdk21u-dev/pull/1993.diff
  Fetch: git fetch https://git.openjdk.org/jdk21u-dev.git pull/1993/head:pull/1993

PR: https://git.openjdk.org/jdk21u-dev/pull/1993