PR Summary

Nested runspace debugging is now supported on non-Windows platforms after Enter-PSHostProcess was added. However, nested debugging was broken because the Windows impersonation code portion was not fully ifdefed out.

This change removes Windows only impersonation code for cross platform builds. It also updates the Windows impersonation flow code to work with dotNet Core.

Repro:

# On one PowerShell shell instance run:
$pid
14931

$ps = [powershell]::Create()
$ps.AddScript('1..20 | % { sleep 1; "Output $_" }').Invoke()

# On second PowerShell shell run:
Enter-PSHostProcess -Id 14931
[Process:14931]: PS > Debug-Runspace -Id 2

Expect:
Should be able to run a nested debug session on script.

Result:
Cannot debug script due to "Unsupported platform error".

PR Checklist

• PR has a meaningful title
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• Summarized changes
• Change is not breaking
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• User-facing changes
  • Not Applicable
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  • User-facing Documentation needed
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• Testing - New and feature
  • Not Applicable or can only be tested interactively
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  • Make sure you've added a new test if existing tests do not effectively test the code changed
    • Add [feature] if the change is significant or affects feature tests