RFR: 8325137: com/sun/management/ThreadMXBean/ThreadCpuTimeArray.java can fail in Xcomp with out of expected range [v2]

[Doug Simon]

> The `com/sun/management/ThreadMXBean/ThreadCpuTimeArray.java` can transiently fail when run with `-Xcomp`. This happens when the compilation of methods on the worker threads interleaves with the 2 calls on the main thread to `mbean.getThreadCpuTime` to get the CPU time for all worker threads.
> 
> The way the test is currently written, the worker threads are all usually waiting on a shared monitor when the 2 timings are taken. That is, in a successful run, the delta between the timings is always 0. When `-Xcomp` compilations kick in at the "wrong" time or take sufficiently long, the expected delta of 100 nanoseconds is easily exceeded.
> 
> It does not make sense to run a timing test with such a small expected delta with `-Xcomp` so this PR simply ignores the test when `-Xcomp` is present.

Doug Simon has updated the pull request incrementally with one additional commit since the last revision:

  fix date in header

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/17675/files
  - new: https://git.openjdk.org/jdk/pull/17675/files/4ff2f7cd..a3bc2653

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=17675&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=17675&range=00-01

  Stats: 1 line in 1 file changed: 0 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/17675.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/17675/head:pull/17675

PR: https://git.openjdk.org/jdk/pull/17675