[jdk25u-dev] RFR: 8365976: G1: Full gc should mark nmethods on stack

[Roland Mesde]

Backporting JDK-8365976: G1: Full gc should mark nmethods on stack.

This PR fixes a regression introduced by JDK-8360540 where full GC stopped marking nmethods on the stack, potentially causing premature code eviction. The fix moves nmethod arming to occur after nmethod registration during full GC, ensuring that nmethods remaining after collection are properly armed and protected from inappropriate eviction.

This depends on https://github.com/openjdk/jdk25u-dev/pull/140

This backport has internal demand.

Ran related tests on linux-x64, linux-aarch64, macos-aarch64 and windows-x64:

make test TEST=test/hotspot/jtreg/vmTestbase/gc

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Depends on: https://git.openjdk.org/jdk25u-dev/pull/140

Commit messages:
 - Backport 57434c73eac9bd6557b09d4a057e3a2a18f382b4

Changes: https://git.openjdk.org/jdk25u-dev/pull/142/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk25u-dev&pr=142&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8365976
  Stats: 3 lines in 2 files changed: 1 ins; 2 del; 0 mod
  Patch: https://git.openjdk.org/jdk25u-dev/pull/142.diff
  Fetch: git fetch https://git.openjdk.org/jdk25u-dev.git pull/142/head:pull/142

PR: https://git.openjdk.org/jdk25u-dev/pull/142