RFR: 8291021: JFR: Only one finished state in ChunkHeader class

Could I have a review of PR that removes the field isFinished in the ChunkHeader class. It's sufficient with the finished field. Testing: jdk/jdk/jfr Thanks Erik ------------- Commit messages: - Initial Changes: https://git.openjdk.org/jdk/pull/9639/files Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=9639&range=00 Issue: https://bugs.openjdk.org/browse/JDK-8291021 Stats: 4 lines in 1 file changed: 0 ins; 2 del; 2 mod Patch: https://git.openjdk.org/jdk/pull/9639.diff Fetch: git fetch https://git.openjdk.org/jdk pull/9639/head:pull/9639 PR: https://git.openjdk.org/jdk/pull/9639