RFR: Merge openjdk/jdk:master

[William Kemper]

This tag included a change to the `CardTable` (base class for `ShenandoahCardTable`) that required a couple of commits to fix up.

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Commit messages:
 - Do not search past last valid index for objects in clean cards
 - Remove '-1' for '+1' removed in JDK-8292912
 - Merge tag 'jdk-20+18' into upstream-merge-test
 - 8294869: Correct failure of RemovedJDKInternals.java after JDK-8294618
 - 8294397: Replace StringBuffer with StringBuilder within java.text
 - 8294734: Redundant override in AES implementation
 - 8294618: Update openjdk.java.net => openjdk.org
 - 8294840: langtools OptionalDependencyTest.java use File.pathSeparator
 - 8289925: Shared code shouldn't reference the platform specific method frame::interpreter_frame_last_sp()
 - 8282900: runtime/stringtable/StringTableCleaningTest.java verify unavailable at this moment
 - ... and 504 more: https://git.openjdk.org/shenandoah/compare/a3799c8d...1b8006a7

The webrevs contain the adjustments done while merging with regards to each parent branch:
 - master: https://webrevs.openjdk.org/?repo=shenandoah&pr=163&range=00.0
 - openjdk/jdk:master: https://webrevs.openjdk.org/?repo=shenandoah&pr=163&range=00.1

Changes: https://git.openjdk.org/shenandoah/pull/163/files
  Stats: 122056 lines in 2353 files changed: 58668 ins; 49130 del; 14258 mod
  Patch: https://git.openjdk.org/shenandoah/pull/163.diff
  Fetch: git fetch https://git.openjdk.org/shenandoah pull/163/head:pull/163

PR: https://git.openjdk.org/shenandoah/pull/163