[jdk21u-dev] RFR: 8340143: Open source several Java2D rendering loop tests.

[Goetz Lindenmaier]

I backport this for parity with 21.0.8-oracle

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Commit messages:
 - Backport 90c2c0b4ad4ee7d2ea149aea771cf81bd666b1dc

Changes: https://git.openjdk.org/jdk21u-dev/pull/1563/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk21u-dev&pr=1563&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8340143
  Stats: 394 lines in 5 files changed: 394 ins; 0 del; 0 mod
  Patch: https://git.openjdk.org/jdk21u-dev/pull/1563.diff
  Fetch: git fetch https://git.openjdk.org/jdk21u-dev.git pull/1563/head:pull/1563

PR: https://git.openjdk.org/jdk21u-dev/pull/1563