[jdk8u-dev] RFR: 8073464: GC workers do not have thread names

[Zhengyu Gu]

Backport for parity with Oracle 8u351.

The original patch does not apply cleanly, applied manully.

Test:

- [x] runtime on Linux x86_64

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Commit messages:
 - Backport a827cdfa1047ee0af30bb454aad2067420103bae

Changes: https://git.openjdk.java.net/jdk8u-dev/pull/56/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk8u-dev&pr=56&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8073464
  Stats: 16 lines in 7 files changed: 8 ins; 2 del; 6 mod
  Patch: https://git.openjdk.java.net/jdk8u-dev/pull/56.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk8u-dev pull/56/head:pull/56

PR: https://git.openjdk.java.net/jdk8u-dev/pull/56