RFR: Merge jdk20

[Jesper Wilhelmsson]

Forwardport JDK 20 -> JDK 21

-------------

Commit messages:
 - Merge remote-tracking branch 'jdk20/master' into Merge_jdk20
 - 8299237: add ArraysSupport.newLength test to a test group
 - 8299230: Use https: in links
 - 8299015: Ensure that HttpResponse.BodySubscribers.ofFile writes all bytes
 - 8299207: [Testbug] Add back test/jdk/java/awt/Graphics2D/DrawPrimitivesTest.java
 - 8298176: remove OpaqueZeroTripGuardPostLoop once main-loop disappears
 - 8299077: [REDO] JDK-4512626 Non-editable JTextArea provides no visual indication of keyboard focus

The webrevs contain the adjustments done while merging with regards to each parent branch:
 - master: https://webrevs.openjdk.org/?repo=jdk&pr=11773&range=00.0
 - jdk20: https://webrevs.openjdk.org/?repo=jdk&pr=11773&range=00.1

Changes: https://git.openjdk.org/jdk/pull/11773/files
  Stats: 572 lines in 15 files changed: 407 ins; 76 del; 89 mod
  Patch: https://git.openjdk.org/jdk/pull/11773.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/11773/head:pull/11773

PR: https://git.openjdk.org/jdk/pull/11773