[jdk23] RFR: 8335475: ClassBuilder incorrectly calculates max_locals in some cases

[Chen Liang]

Please review this clean backport of #19981 onto JDK 23, fixing `StackMapGenerator` generating static methods with no declared local variable a max local of 1.

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Commit messages:
 - Backport 1ef34c183315b70ddc27c177a2867e30132609f5

Changes: https://git.openjdk.org/jdk/pull/19993/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=19993&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8335475
  Stats: 32 lines in 2 files changed: 28 ins; 0 del; 4 mod
  Patch: https://git.openjdk.org/jdk/pull/19993.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/19993/head:pull/19993

PR: https://git.openjdk.org/jdk/pull/19993