[jdk25u-dev] RFR: 8373946: Synth ProgressBarUI implementation confuses background painting with border painting

[Goetz Lindenmaier]

I backport this for parity with 25.0.3-oracle.

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Commit messages:
 - Backport fe5911c7695283cb76b3d95877138b0b15bc0ba4

Changes: https://git.openjdk.org/jdk25u-dev/pull/122/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk25u-dev&pr=122&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8373946
  Stats: 237 lines in 3 files changed: 123 ins; 110 del; 4 mod
  Patch: https://git.openjdk.org/jdk25u-dev/pull/122.diff
  Fetch: git fetch https://git.openjdk.org/jdk25u-dev.git pull/122/head:pull/122

PR: https://git.openjdk.org/jdk25u-dev/pull/122