Inline remaining usages of OpenProcess on Unix

[am11]

Two usages of OpenProcess and one of OpenProcessMemory.

Follow-up: #127604 (comment).

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[janvorli]

LGTM, thank you!

[jkotas]

@am11 Have you done any ad-hoc testing on this to validate that the debugging is not broken?

@janvorli @tommcdon Do you think it is worth it to run some of the internal diagnostics tests on this PR before merging?

[jkotas]

Looks great otherwise

[am11]

@am11 Have you done any ad-hoc testing on this to validate that the debugging is not broken?

I have done vscode testing on macOS, killing the process when debugger is running does give the same behavior as before. Though I'm not sure if that's conclusive / sufficient amount of testing? 👀

[janvorli]

@janvorli @tommcdon Do you think it is worth it to run some of the internal diagnostics tests on this PR before merging?

I'll run the private diagnostic tests with it.

[am11]

@janvorli, thanks for looking into it. I'm working on part B of this refactoring which will be in the next PR. It involves inlining wait subsystem usage at the callsite while deduplicating stuff, with massive cleanups in PAL; code would end up using the same familiar pthread APIs with minimum synchronization work. The sophisticated part of this Win32 emulation has been largely unused ever since the managed wait subsystem landed in .NET 11, so technically the remaining few native usages don't need to go through the PAL layer at all.

Heads up that round 2 will likely need your and Tom's help running the internal diagnostics test suites against it. 🙂

[janvorli]

@am11 that is awesome!

[janvorli]

@am11 the diagnostic tests have the same pass rate with and without your change.