RFR: 8364628: Serial: Refactor SerialHeap::mem_allocate_work

[Paul Hohensee]

On Mon, 4 Aug 2025 10:01:15 GMT, Albert Mingkun Yang <ayang at openjdk.org> wrote:

> Extract out old-gen allocation outside the critical-region to streamline the flow in `mem_allocate_work`.
> 
> Test: tier1-5

There's quite a lot of duplicate code in all four of these files. Perhaps take the opportunity to consolidate?

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PR Review: https://git.openjdk.org/jdk/pull/26619#pullrequestreview-3099036817