RFR: 8342644: Optimize InvokerBytecodeGenerator for using ClassFile API

[Shaojin Wen]

Cache commonly used classDesc to avoid creating ReferenceClassDescImpl every time

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Commit messages:
 - cache ClassDesc MH/BMH/DMH

Changes: https://git.openjdk.org/jdk/pull/21580/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=21580&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8342644
  Stats: 15 lines in 1 file changed: 12 ins; 0 del; 3 mod
  Patch: https://git.openjdk.org/jdk/pull/21580.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/21580/head:pull/21580

PR: https://git.openjdk.org/jdk/pull/21580