Integrated: Merge openjdk/jdk:master

[William Kemper]

Merges tag jdk-21+15

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

Commit messages:
 - Remove unused card table clear method too
 - Merge tag 'jdk-21+15' into merge-jdk-21-15
 - 8304134: jib bootstrapper fails to quote filename when checking download filetype
 - 8301498: Replace NULL with nullptr in cpu/x86
 - 8304089: Convert TraceDependencies to UL
 - 8294972: Convert jdk.jlink internal plugins to use the Classfile API
 - 8304657: G1: Rename set_state_empty to set_state_untracked
 - 8304144: G1: Remove unnecessary is_survivor check in G1ClearCardTableTask
 - 8304286: java/net/SocketOption/OptionsTest.java failing after JDK-8302659
 - 8303804: Fix some errors of If-VectorTest and CMove-VectorTest
 - ... and 65 more: https://git.openjdk.org/shenandoah/compare/a5d1a9d8...a0c67bac

The webrevs contain the adjustments done while merging with regards to each parent branch:
 - master: https://webrevs.openjdk.org/?repo=shenandoah&pr=234&range=00.0
 - openjdk/jdk:master: https://webrevs.openjdk.org/?repo=shenandoah&pr=234&range=00.1

Changes: https://git.openjdk.org/shenandoah/pull/234/files
  Stats: 11524 lines in 523 files changed: 6474 ins; 2392 del; 2658 mod
  Patch: https://git.openjdk.org/shenandoah/pull/234.diff
  Fetch: git fetch https://git.openjdk.org/shenandoah.git pull/234/head:pull/234

PR: https://git.openjdk.org/shenandoah/pull/234