RFR: 8294961: Convert java.base/java.lang.reflect.ProxyGenerator to use the Classfile API to generate proxy classes [v3]

[Adam Sotona]

> java.base java.lang.reflect.ProxyGenerator uses ASM to generate proxy classes.
> 
> This patch converts it to use Classfile API.
> 
> It is continuation of https://github.com/openjdk/jdk/pull/10991
> 
> Any comments and suggestions are welcome.
> 
> Please review.
> 
> Thank you,
> Adam

Adam Sotona has updated the pull request incrementally with two additional commits since the last revision:

 - performance improvements
 - SplitConstantPool performance fix

-------------

Changes:
  - all: https://git.openjdk.org/jdk/pull/17121/files
  - new: https://git.openjdk.org/jdk/pull/17121/files/a21fb264..75e31e3a

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=17121&range=02
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=17121&range=01-02

  Stats: 76 lines in 2 files changed: 21 ins; 10 del; 45 mod
  Patch: https://git.openjdk.org/jdk/pull/17121.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/17121/head:pull/17121

PR: https://git.openjdk.org/jdk/pull/17121