RFR: 7979: Reduce allocation rate in ParserStats

Mon Nov 21 09:53:03 UTC 2022

Somewhat surprisingly, the capturing lambdas and the `Long`s being updated here are one of the highest allocation sources when using jmc-common as a backend library, this PR has reduced our allocation rate by about 5%.

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

Commit messages:
 - 7979: Reduce allocation rate in ParserStats

Changes: https://git.openjdk.org/jmc/pull/455/files
 Webrev: https://webrevs.openjdk.org/?repo=jmc&pr=455&range=00
  Issue: https://bugs.openjdk.org/browse/JMC-7979
  Stats: 34 lines in 1 file changed: 5 ins; 13 del; 16 mod
  Patch: https://git.openjdk.org/jmc/pull/455.diff
  Fetch: git fetch https://git.openjdk.org/jmc pull/455/head:pull/455

PR: https://git.openjdk.org/jmc/pull/455