RFR: 8339197: GenShen: Adding Generation and Evacuation Information JFR Logging [v2]

[Satyen Subramaniam]

> Adding `ShenandoahEvacInfo` event and modifying existing logging for Concurrent Reset and Final Roots events to include generation for Generational Shenandoah GC.

Satyen Subramaniam has updated the pull request incrementally with four additional commits since the last revision:

 - Adding additional fields to ShenandoahEvacInfo
 - Updating copyright message
 - Updating .jfc files to include ShenandoahEvacInfo
 - Updating regionsImmediate to use uint

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Changes:
  - all: https://git.openjdk.org/shenandoah/pull/489/files
  - new: https://git.openjdk.org/shenandoah/pull/489/files/7b7a8c1b..e434531c

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=shenandoah&pr=489&range=01
 - incr: https://webrevs.openjdk.org/?repo=shenandoah&pr=489&range=00-01

  Stats: 75 lines in 7 files changed: 70 ins; 0 del; 5 mod
  Patch: https://git.openjdk.org/shenandoah/pull/489.diff
  Fetch: git fetch https://git.openjdk.org/shenandoah.git pull/489/head:pull/489

PR: https://git.openjdk.org/shenandoah/pull/489