RFR: Merge jdk8u:master

[Andrew John Hughes]

Merge jdk8u412-b07

GHA builds will not work until [JDK-8293107](https://bugs.openjdk.org/browse/JDK-8293107) is merged in 8u462-b01

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Commit messages:
 - Merge jdk8u412-b07
 - 8321408: Add Certainly roots R1 and E1

The merge commit only contains trivial merges, so no merge-specific webrevs have been generated.

Changes: https://git.openjdk.org/shenandoah-jdk8u/pull/72/files
  Stats: 93 lines in 4 files changed: 89 ins; 0 del; 4 mod
  Patch: https://git.openjdk.org/shenandoah-jdk8u/pull/72.diff
  Fetch: git fetch https://git.openjdk.org/shenandoah-jdk8u.git pull/72/head:pull/72

PR: https://git.openjdk.org/shenandoah-jdk8u/pull/72