Integrated: 8343649: Shenandoah: ShenandoahEvacInfo event does not follow JFR guidelines

[Satyen Subramaniam]

Renaming ShenandoahEvacInfo event to ShenandoahEvacuationInformation (to comply with JFR guidelines) and adding test for event functionality.

Tested with tier 1, tier 2, and tier 3 tests.

-------------

Commit messages:
 - Adding ShenandoahEvacuationInformation Event Tests
 - Renaming ShenandoahEvacInfo to ShenandoahEvacuationInformation

Changes: https://git.openjdk.org/shenandoah/pull/533/files
  Webrev: https://webrevs.openjdk.org/?repo=shenandoah&pr=533&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8343649
  Stats: 127 lines in 9 files changed: 114 ins; 0 del; 13 mod
  Patch: https://git.openjdk.org/shenandoah/pull/533.diff
  Fetch: git fetch https://git.openjdk.org/shenandoah.git pull/533/head:pull/533

PR: https://git.openjdk.org/shenandoah/pull/533