[jdk17u] RFR: 8271722: [TESTBUG] gc/g1/TestMixedGCLiveThreshold.java can fail if G1 Full GC uses >1 workers

[Richard Reingruber]

Hi all,

this pull request contains a clean backport of commit 4abe5311 from the openjdk/jdk repository.
I would like to backport this to 17u to avoid false positives in 17u tests.
The commit being backported was authored by Richard Reingruber on 5 Aug 2021 and was reviewed by Albert Mingkun Yang and Thomas Schatzl.

Thanks!
Richard.

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

Commit messages:
 - Backport 4abe5311407c68d04fb0babb87fa279e35d5fabc

Changes: https://git.openjdk.java.net/jdk17u/pull/75/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk17u&pr=75&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8271722
  Stats: 2 lines in 1 file changed: 2 ins; 0 del; 0 mod
  Patch: https://git.openjdk.java.net/jdk17u/pull/75.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk17u pull/75/head:pull/75

PR: https://git.openjdk.java.net/jdk17u/pull/75