RFR: 8254167 G1: Record regions where evacuation failed to provide targeted iteration

[Hamlin Li]

This is a try to optimize evcuation failure for regions.
I record evacuation failed regions, and iterate these regions directly rather than iterate the whole cset.
The implementation reuses and refactors some of the existing data in g1CollectedHeap (_regions_failed_evacuation, _num_regions_failed_evacuation), and records these regions in an array, and iterate this array later in post evacuation phase.

I have 2 implementations:

- 1) CHT
- 2) bitmap (reuse _regions_failed_evacuation in g1CollectedHeap)

This implementation does not consider work distribution as mentioned in JDK-8254167 yet. But seems it already get better&stable performance gain than origin. We could improve it further later if work distribution is necessary.

I will attach the perf data in JBS.

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Commit messages:
 - merge with existing classes
 - Initial commit

Changes: https://git.openjdk.java.net/jdk/pull/5272/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=5272&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8254167
  Stats: 218 lines in 6 files changed: 200 ins; 11 del; 7 mod
  Patch: https://git.openjdk.java.net/jdk/pull/5272.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/5272/head:pull/5272

PR: https://git.openjdk.java.net/jdk/pull/5272