RFR: 8347287: JFR: Remove use of Security Manager

[Erik Gahlin]

Could I have a review of PR that removes Java related code not needed when the Security Manager is disabled. 

Testing: tier1 + test/jdk/jdk/jfr

Thanks
Erik

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Commit messages:
 - Update copyright
 - Update specification in seperate issue
 - Remove mistakenly added directory
 - Fix copyright year
 - Remove whitespace
 - Remove whitespace
 - Update copyright to 2025
 - Initial

Changes: https://git.openjdk.org/jdk/pull/22787/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=22787&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8347287
  Stats: 1986 lines in 86 files changed: 197 ins; 1380 del; 409 mod
  Patch: https://git.openjdk.org/jdk/pull/22787.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/22787/head:pull/22787

PR: https://git.openjdk.org/jdk/pull/22787