RFR: 8340831: Simplify simple validation for class definition in MethodHandles.Lookup [v2]

[Chen Liang]

> `MethodHandles.Lookup` defines a `ClassFile` for simple validations; it is unnecessary and can be scalarized manually. The removal of `ClassFile` class is also slightly helpful for bootstrap by reducing class loading. Also improved class file version checking in `VM` class.

Chen Liang has updated the pull request incrementally with one additional commit since the last revision:

  Rename to internalName where possible

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Changes:
  - all: https://git.openjdk.org/jdk/pull/21170/files
  - new: https://git.openjdk.org/jdk/pull/21170/files/bd90f8d9..c172d126

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=21170&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=21170&range=00-01

  Stats: 15 lines in 1 file changed: 0 ins; 4 del; 11 mod
  Patch: https://git.openjdk.org/jdk/pull/21170.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/21170/head:pull/21170

PR: https://git.openjdk.org/jdk/pull/21170