RFR: 8301599: Serial: Refactor nested closures in DefNewGeneration

[Ivan Walulya]

On Wed, 1 Feb 2023 10:13:25 GMT, Albert Mingkun Yang <ayang at openjdk.org> wrote:

> Simple refactoring broken into two commits:
> 
> 1. Rename `KeepAliveClosure`.
> 2. Extract and move closures to cpp file.
> 
> Test: hotspot_gc

Marked as reviewed by iwalulya (Reviewer).

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PR: https://git.openjdk.org/jdk/pull/12359