RFR: 8291022: JFR: Reduce logging in ChunkHeader constructor

[Erik Gahlin]

Could I have review of change that removes some unnecessary and unreliable logging.

Testing: jdk/jdk/jfr

Thanks
Erik

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Commit messages:
 - Remove traling whitepace
 - Initial

Changes: https://git.openjdk.org/jdk/pull/9640/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=9640&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8291022
  Stats: 16 lines in 1 file changed: 6 ins; 2 del; 8 mod
  Patch: https://git.openjdk.org/jdk/pull/9640.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/9640/head:pull/9640

PR: https://git.openjdk.org/jdk/pull/9640