RFR: 8365885: Clean up constant pool reflection native code

[Ioi Lam]

On Wed, 20 Aug 2025 21:29:29 GMT, Chen Liang <liach at openjdk.org> wrote:

> When I was trying to reuse this constant pool reflection for assembly phase indy argument validation, I noted the JNI code has a lot of confusing arguments. In particular, the JVM_ConstantPoolGetSize is wrong because of argument confusion. We should remove the unused arguments to reduce confusion.

LGTM

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Marked as reviewed by iklam (Reviewer).

PR Review: https://git.openjdk.org/jdk/pull/26870#pullrequestreview-3152454131