RFR: 8316581: Improve performance of Symbol::print_value_on()

[Thomas Schatzl]

Hi all,

  please review this (hopefully correct) optimization of `Symbol::print_value_on()`; investigation into class unloading time distribution showed that a lot of time is spent in the `UnloadingEventLog::log()` call (25+%, see CR).

The reason seems to be the use of `outputStream::print()` without any need for formatting.

This seems to decrease time spent in this logging by almost 10x.

Testing: hs_err output seems still be the same, GHA

Thanks,
  Thomas

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Commit messages:
 - improve symbol::print_value_on() performance

Changes: https://git.openjdk.org/jdk/pull/15838/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=15838&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8316581
  Stats: 6 lines in 1 file changed: 0 ins; 2 del; 4 mod
  Patch: https://git.openjdk.org/jdk/pull/15838.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/15838/head:pull/15838

PR: https://git.openjdk.org/jdk/pull/15838