RFR: 8266936: Add a finalization JFR event [v8]

[Markus Grönlund]

> Greetings,
> 
> Object.finalize() was deprecated in JDK9. There is an ongoing effort to replace and mitigate Object.finalize() uses in the JDK libraries; please see https://bugs.openjdk.java.net/browse/JDK-8253568 for more information. 
> 
> We also like to assist users in replacing and mitigating uses in non-JDK code.
> 
> Hence, this changeset adds a periodic JFR event to help identify which classes are overriding Object.finalize().
> 
> Thanks
> Markus

Markus Grönlund has updated the pull request incrementally with one additional commit since the last revision:

  enqueued data point

-------------

Changes:
  - all: https://git.openjdk.java.net/jdk/pull/4731/files
  - new: https://git.openjdk.java.net/jdk/pull/4731/files/7d63693f..5da3bb89

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=4731&range=07
 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=4731&range=06-07

  Stats: 62 lines in 5 files changed: 46 ins; 8 del; 8 mod
  Patch: https://git.openjdk.java.net/jdk/pull/4731.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/4731/head:pull/4731

PR: https://git.openjdk.java.net/jdk/pull/4731