RFR: 8295344: Harden runtime/StackGuardPages/TestStackGuardPages.java [v2]

[Johan Sjölen]

> There are multiple ways which the stack guard pages tests can be hardened:
> - Rewritten the Java part of the test using ProcessTools.executeProcess(ProcessBuilder pb) which will make stdout/stderr be consistently logged and debugging much easier.
> - Split up initial/other thread into 2 tests
> - Split up Java thread tests and native thread tests into two separate files
> - Check more error conditions in the C code
> - Instead of recursing and creating stack frames, just `alloca()` and poke until we hit a `SIGSEGV`.
> 
> The goal is that this will help us out with  [JDK-8293452](https://bugs.openjdk.org/browse/JDK-8293452).

Johan Sjölen has updated the pull request incrementally with one additional commit since the last revision:

  Remove from ProblemList.txt

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Changes:
  - all: https://git.openjdk.org/jdk/pull/12386/files
  - new: https://git.openjdk.org/jdk/pull/12386/files/f02c9b44..96b40c9f

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=12386&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=12386&range=00-01

  Stats: 1 line in 1 file changed: 0 ins; 1 del; 0 mod
  Patch: https://git.openjdk.org/jdk/pull/12386.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/12386/head:pull/12386

PR: https://git.openjdk.org/jdk/pull/12386