RFR: 8297006: JFR: AbstractEventStream should not hold thread instance

[Erik Gahlin]

Could I have a review of a PR that removes an unnecessary reference to a thread. This could potentially become a memory leak.

Testing: test/jdk/jdk/jfr

Thanks
Erik

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Commit messages:
 - Initial

Changes: https://git.openjdk.org/jdk/pull/11166/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=11166&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8297006
  Stats: 4 lines in 1 file changed: 0 ins; 2 del; 2 mod
  Patch: https://git.openjdk.org/jdk/pull/11166.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/11166/head:pull/11166

PR: https://git.openjdk.org/jdk/pull/11166