RFR: 8364176: Serial: Group all class unloading logic at the end of marking phase

[Sangheon Kim]

On Mon, 28 Jul 2025 08:54:25 GMT, Albert Mingkun Yang <ayang at openjdk.org> wrote:

> Simple moving some classunloading logic inside `SerialFullGC`.
> 
> Test: tier1

Looks good.

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Marked as reviewed by sangheki (Reviewer).

PR Review: https://git.openjdk.org/jdk/pull/26499#pullrequestreview-3076491468