RFR: 8333377: Migrate Generic Signature parsing to ClassFile API

[Chen Liang]

Replace the legacy sun reflect generics tree API with the classfile signature model API. This allows us to maintain just one set of API for future signature changes like null restricted types. This should be less invasive than #19281.

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Commit messages:
 - Use classfile signature tree parsing

Changes: https://git.openjdk.org/jdk/pull/29510/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=29510&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8333377
  Stats: 2206 lines in 42 files changed: 82 ins; 2043 del; 81 mod
  Patch: https://git.openjdk.org/jdk/pull/29510.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/29510/head:pull/29510

PR: https://git.openjdk.org/jdk/pull/29510