RFR: 8349088: De-virtualize Codeblob and nmethod [v3]

[Vladimir Kozlov]

> Remove virtual methods from CodeBlob and nmethod to simplify saving/restoring in Leyden AOT cache. It avoids the need to patch hidden VPTR pointer to class's virtual table.
> 
> Added C++ static asserts to make sure no virtual methods are added in a future.
> 
> Fixed/cleaned SA code which process CodeBlob and its subclasses. Use `CodeBlob::_kind` field value to determine the type of blob.
> 
> Tested tier1-5, hs-tier6-rt (for JFR testing), stress, xcomp

Vladimir Kozlov has updated the pull request incrementally with one additional commit since the last revision:

  Add CodeBlob proxy vtable

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Changes:
  - all: https://git.openjdk.org/jdk/pull/23533/files
  - new: https://git.openjdk.org/jdk/pull/23533/files/dda20f0b..43ae0ed2

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=23533&range=02
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=23533&range=01-02

  Stats: 322 lines in 13 files changed: 175 ins; 90 del; 57 mod
  Patch: https://git.openjdk.org/jdk/pull/23533.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/23533/head:pull/23533

PR: https://git.openjdk.org/jdk/pull/23533