RFR: 8257876: Avoid Reference.isEnqueued in tests [v3]

[Kim Barrett]

On Tue, 8 Dec 2020 17:30:11 GMT, Mandy Chung <mchung at openjdk.org> wrote:

>> Kim Barrett has updated the pull request with a new target base due to a merge or a rebase. The incremental webrev excludes the unrelated changes brought in by the merge/rebase. The pull request contains five additional commits since the last revision:
>> 
>>  - Merge branch 'master' into no_isenqueued
>>  - move REMOVE and RETAIN decls and init
>>  - update WeakReferenceGC test
>>  - update ReferenceQueue test
>>  - update ReferencesGC test
>
> Marked as reviewed by mchung (Reviewer).

Thanks for reviews @mlchung and @tschatzl

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PR: https://git.openjdk.java.net/jdk/pull/1691