RFR: 8374698: Stub names should look more like identifiers [v2]

[Aleksey Shipilev]

> Noticed this when looking at disassembly. Cosmetic issue in [JDK-8360707](https://bugs.openjdk.org/browse/JDK-8360707) makes the stub identifiers look fairly weird:
> 
> 
> 0x0000786da3c1a6f2: call Stub::Stub Generator lookup_secondary_supers_table_slow_path_stub
>     ; {runtime_call Stub::Stub Generator lookup_secondary_supers_table_slow_path_stub}
> 
> 
> Notice "Stub Generator" in the middle of the stub identifier.
> 
> After the fix:
> 
> 
> 0x00007f357bc1a3f2:   call   Stub::lookup_secondary_supers_table_slow_path_stub (stub gen)
>      ; {runtime_call Stub::lookup_secondary_supers_table_slow_path_stub (stub gen)}

Aleksey Shipilev has updated the pull request incrementally with one additional commit since the last revision:

  Of course there are asserts that verify stub names directly

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/29080/files
  - new: https://git.openjdk.org/jdk/pull/29080/files/e3f01c75..eae99d56

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=29080&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=29080&range=00-01

  Stats: 16 lines in 4 files changed: 10 ins; 3 del; 3 mod
  Patch: https://git.openjdk.org/jdk/pull/29080.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/29080/head:pull/29080

PR: https://git.openjdk.org/jdk/pull/29080