RFR: 8375747: ZGC: ZForwardingTest is unable to commit memory on Windows [v2]

[Stefan Karlsson]

> The ZForwardingTest gtest first reserves memory via the ZGC APIs to do so and then uses the generic `os::commit_memory(...)` to commit the memory. That is problematic on Windows because the two APIs are not compatible there. I've updated the test to use ZGC's APIs to commit and map memory instead.
> 
> Thanks to @roberttoyonaga for finding this and helping out diagnosing this issue!
> 
> The patch also adds some tiny fixes to the assert code that mislead me while prototyping this.
> 
> I'll run this through tier1 testing.

Stefan Karlsson has updated the pull request incrementally with one additional commit since the last revision:

  Restructure setup and teardown

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/29471/files
  - new: https://git.openjdk.org/jdk/pull/29471/files/7180a1d7..ec3120cd

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=29471&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=29471&range=00-01

  Stats: 15 lines in 1 file changed: 6 ins; 7 del; 2 mod
  Patch: https://git.openjdk.org/jdk/pull/29471.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/29471/head:pull/29471

PR: https://git.openjdk.org/jdk/pull/29471