RFR: 8287596: Reorg jdk.test.lib.util.ForceGC [v10]

[Xue-Lei Andrew Fan]

> This is a follow up update per comments in [JDK-8287384 PR](https://urldefense.com/v3/__https://github.com/openjdk/jdk/pull/8907__;!!ACWV5N9M2RV99hQ!NNGX7uEj58t7UHOcS2PbUgT_R8PW8A2xNlmJ5N8WuCcgG8EPOLJBHAjRiwhXq_NhJ33K0VrDlHQxNLJpVy9XSw$ ).  The tier1 and tier2 test in open part looks good to me.  Please help to run Mach5 just case the closed test cases are impacted.

Xue-Lei Andrew Fan has updated the pull request with a new target base due to a merge or a rebase. The pull request now contains 13 commits:

 - Master
 - use Reference.refersTo
 - remove trailing whitespaces
 - use timeout factor
 - Merge
 - Merge master
 - Merge
 - add timeout parameter
 - rollback is not in this branch
 - rollback JDK-8287384
 - ... and 3 more: https://git.openjdk.org/jdk/compare/47b86690...0f196282

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Changes: https://git.openjdk.org/jdk/pull/8979/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=8979&range=09
  Stats: 93 lines in 10 files changed: 14 ins; 38 del; 41 mod
  Patch: https://git.openjdk.org/jdk/pull/8979.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/8979/head:pull/8979

PR: https://git.openjdk.org/jdk/pull/8979