RFR: 8293544: G1: Add comment in G1BarrierSetC1::pre_barrier

[Albert Mingkun Yang]

On Thu, 8 Sep 2022 13:30:58 GMT, Albert Mingkun Yang <ayang at openjdk.org> wrote:

> A comment-only change in G1 pre-barrier to explain the redundant is-marking-active check.

Thanks for the review.

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PR: https://git.openjdk.org/jdk/pull/10219