RFR: 8292541: [Metrics] Reported memory limit may exceed physical machine memory [v4]

[Jonathan Dowland]

> When the container memory exceeds the physical host's memory, the Java metrics reporting is wrong.
> 
> https://bugs.openjdk.org/browse/JDK-8292541
> 
> This is the equivalent core-libs fix for Hotspot's [JDK-8292083](https://bugs.openjdk.org/browse/JDK-8292083)
> (https://github.com/openjdk/jdk/pull/9880)

Jonathan Dowland has updated the pull request incrementally with two additional commits since the last revision:

 - use pre-defined constant over magic number
 - Address style nits

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/10017/files
  - new: https://git.openjdk.org/jdk/pull/10017/files/ff6990cb..01d07ab4

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=10017&range=03
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=10017&range=02-03

  Stats: 5 lines in 1 file changed: 0 ins; 0 del; 5 mod
  Patch: https://git.openjdk.org/jdk/pull/10017.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/10017/head:pull/10017

PR: https://git.openjdk.org/jdk/pull/10017