[jdk11u-dev] RFR: 8231111: Cgroups v2: Rework Metrics in java.base so as to recognize unified hierarchy

[Zhengyu Gu]

This is a followup backport for Cgroup v2 support.

The original patch does not apply cleanly, due to context differences and some of out-of-order backports, conflicts were resolved manually.

In additional:

1) Include partial backport of JDK-8250627.
    - Renamed `Metrics.c` =>  `CgroupMetrics.c`
    - Added native method `isUseContainerSupport()` to `CgroupMetrics.java`
    - Return instance only if `isUseContainerSupport()` is enabled.
   
2) Add `createTempDirectory()` method to `test/lib/jdk/test/lib/Utils.java` for `TestCgroupSubsystemController.java` test

3) Add `import jdk.test.lib.process.OutputAnalyzer;` to `TestDockerMemoryMetrics.java`

Test:

- [x] jtreg containers/docker test on Ubuntu 20.04.4 LTS
- [x] jdk/test/lib/containers/cgroup
- [x] jdk/internal/platform/docker

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Depends on: https://git.openjdk.java.net/jdk11u-dev/pull/840

Commit messages:
 - Fix tests
 - Add parital 8250627 backport
 - Backport 4def210a22faaec6b47912dd314e6365ea48d28f

Changes: https://git.openjdk.java.net/jdk11u-dev/pull/863/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk11u-dev&pr=863&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8231111
  Stats: 5364 lines in 32 files changed: 3585 ins; 1622 del; 157 mod
  Patch: https://git.openjdk.java.net/jdk11u-dev/pull/863.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk11u-dev pull/863/head:pull/863

PR: https://git.openjdk.java.net/jdk11u-dev/pull/863