RFR: 8265012: Shenandoah: Backout JDK-8264718

[Aleksey Shipilev]

On Fri, 9 Apr 2021 21:14:22 GMT, Zhengyu Gu <zgu at openjdk.org> wrote:

> It turns out that enquening string deduplication candidates during concurrent root scanning may result lock rank inversion between stack watermark lock and string dedup queue lock, if the scanning is triggered by stack watermark and dedup buffer happens to be full.
> 
> Backout JDK-8264718 for now, will retry after Kim's string deduplication refactoring.
> 
> Test:
> - [x] hotspot_gc_shenandoah

Looks fine.

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Marked as reviewed by shade (Reviewer).

PR: https://git.openjdk.java.net/jdk/pull/3423