RFR: 8263236: runtime/os/TestTracePageSizes.java fails on old kernels [v4]

[Aleksey Shipilev]

> See the bug report for details. On some kernels, the madvise hint is not reflected in `/proc/smaps`. Instead, we can use a secondary evidence and read `AnonHugePages`.
> 
> Additional testing:
>  - [x] Test with kernel 5.4.0 (still passes)
>  - [x] Test with kernel 4.9.0 (used to fail, now passes)

Aleksey Shipilev has updated the pull request incrementally with two additional commits since the last revision:

 - No tabs
 - Just ignore on older kernels

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

Changes:
  - all: https://git.openjdk.java.net/jdk/pull/3415/files
  - new: https://git.openjdk.java.net/jdk/pull/3415/files/c7a6136c..5bf7827c

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=3415&range=03
 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=3415&range=02-03

  Stats: 81 lines in 1 file changed: 21 ins; 40 del; 20 mod
  Patch: https://git.openjdk.java.net/jdk/pull/3415.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/3415/head:pull/3415

PR: https://git.openjdk.java.net/jdk/pull/3415