[jdk21u-dev] RFR: 8341453: java/awt/a11y/AccessibleJTableTest.java fails in some cases where the test tables are not visible

[Goetz Lindenmaier]

I backport this for parity with 21.0.7-oracle

The issue addressed by this change is fixed.
But the test does not exactly do what is requested by the description.
Maybe the description is shaky, or mac behaves different from windows and 
the description is not tailerd for this.  E.g., it does not anouce the cell position if
entering the table. It does so when reordering the columns. Also, some of the 
buttons in the third test are not visible.  They work, though.
I verified this is the same if run on jdk head.

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Commit messages:
 - Backport f1f15370fa26e4c1121abadb8938c0126c6f4f24

Changes: https://git.openjdk.org/jdk21u-dev/pull/1340/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk21u-dev&pr=1340&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8341453
  Stats: 22 lines in 1 file changed: 10 ins; 6 del; 6 mod
  Patch: https://git.openjdk.org/jdk21u-dev/pull/1340.diff
  Fetch: git fetch https://git.openjdk.org/jdk21u-dev.git pull/1340/head:pull/1340

PR: https://git.openjdk.org/jdk21u-dev/pull/1340