[jdk17u-dev] RFR: 8271506: Add ResourceHashtable support for deleting selected entries

[Goetz Lindenmaier]

I backport this as prerequisite to JDK-8274944 which calls the new method unlink().

I had to adapt the code to work in jdk17 because ""JDK-8269004: Implement ResizableResourceHashtable" is missing in 17.

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Commit messages:
 - Backport f15d6cbcaf191b9718ab51b1e8b72938c0abdd6b

Changes: https://git.openjdk.java.net/jdk17u-dev/pull/132/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk17u-dev&pr=132&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8271506
  Stats: 50 lines in 2 files changed: 50 ins; 0 del; 0 mod
  Patch: https://git.openjdk.java.net/jdk17u-dev/pull/132.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk17u-dev pull/132/head:pull/132

PR: https://git.openjdk.java.net/jdk17u-dev/pull/132