RFR: 8293499: Provide jmod compression level option [v2]

[Jaikiran Pai]

On Mon, 12 Sep 2022 10:48:16 GMT, Aleksey Shipilev <shade at openjdk.org> wrote:

>> I have been looking into `make clean-images images` performance, and realized jmod keeps compressing files with default compression level. Tuning that toward lighter compression levels improves build performance considerably, without a heavy loss in *.jmod sizes. 
>> 
>> This PR allows JMOD to select the compression level. Follow-ups would use this in the build system, see #10214.
>> 
>> This change nominally requires CSR, but I would like to gauge the reaction to this patch first, before submitting a formal CSR. The interesting asymmetry against `jlink` is: `jlink` provides `--compress` option that only takes `2` for "ZIP compression". (Separately, we could argue if it would be beneficial to add `--compression-level` to `jlink` as well, so to select the compression level there too.)
>
> Aleksey Shipilev has updated the pull request with a new target base due to a merge or a rebase. The incremental webrev excludes the unrelated changes brought in by the merge/rebase. The pull request contains three additional commits since the last revision:
> 
>  - Only accept --compression-level when creating the archive
>  - Merge branch 'master' into JDK-8293499-jmod-compression-level
>  - Fix

Thank you for the changes Aleksey. They look fine to me (except for that one minor error message related issue which I added a comment for). I haven't given the latest changes a try, but the new test you added to verify that the command fails in other modes when `--compression-level` will cover it.

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PR: https://git.openjdk.org/jdk/pull/10213