RFR: 8296229: JFR: jfr tool should print unsigned values correctly [v2]

[Erik Gahlin]

> Could I have a review of PR that fixes so unsigned numbers are printed correctly in the jfr tool.
> 
> Testing:
> test/jdk/jdk/jfr
> test/jdk/jdk/security/logging/
> 
> Thanks
> Erik

Erik Gahlin has updated the pull request with a new target base due to a merge or a rebase. The pull request now contains two commits:

 - Merge
 - Initial

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Changes: https://git.openjdk.org/jdk/pull/11039/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=11039&range=01
  Stats: 77 lines in 15 files changed: 37 ins; 1 del; 39 mod
  Patch: https://git.openjdk.org/jdk/pull/11039.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/11039/head:pull/11039

PR: https://git.openjdk.org/jdk/pull/11039