RFR: 8364103: Convert existing sprintf-chains to stringStream [v4]

[Paul Hübner]

> Hi all,
> 
> This PR refactors `javaClasses`' `print_stack_element_to_stream` to use a `stringStream` instead of manually maintaining a buffer with `os::snprintf` chains.
> 
> The JBS issue outlines to do this for all occurrences of `snprintf`-like chains. The majority of the calls to `os::snprintf`, `os::snprintf_checked`, `os::vsnprintf`, etc. occur just once. `LogTagSet::vwrite` is the only place to my knowledge where there remains a `vsnprintf` chain using manual buffer arithmetic. After consulting @jdksjolen, we decided that due to the
> a) low-level nature of the code, and 
> b) widespread usage of logging in the VM, 
> this should probably warrant a larger discussion and/or separate issue. Personally, I feel like the performance & correctness risks of introducing a high-level abstraction here outweighs the benefits. 
> 
> I've run tests with JDK tiers 1-3 on macOS (AArch64, x64), Linux (AArch64, x64), and Windows (x64); all green.

Paul Hübner has updated the pull request incrementally with one additional commit since the last revision:

  Update src/hotspot/share/classfile/javaClasses.cpp
  
  Co-authored-by: David Holmes <62092539+dholmes-ora at users.noreply.github.com>

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Changes:
  - all: https://git.openjdk.org/jdk/pull/26894/files
  - new: https://git.openjdk.org/jdk/pull/26894/files/3a87b884..21049190

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=26894&range=03
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=26894&range=02-03

  Stats: 4 lines in 1 file changed: 0 ins; 3 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/26894.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/26894/head:pull/26894

PR: https://git.openjdk.org/jdk/pull/26894