Console.Unix: fix, make CancelKeyPress work when input is redirected.

[tmds]

Fixes #51221.

Regressed in 5.0: #34297.

@jeffhandley @adamsitnik @carlossanlop @jozkee ptal

[ghost]

Tagging subscribers to this area: @carlossanlop
See info in area-owners.md if you want to be subscribed.

Issue Details

---

Fixes #51221.

Regressed in 5.0: #34297.

@jeffhandley @adamsitnik @carlossanlop @jozkee ptal

Author:	tmds
Assignees:	-
Labels:	area-System.Console
Milestone:	-

[tmds]

CI is not too happy about this change:

Process terminated. Assertion failed.
   at System.Console.get_Out() in /_/src/libraries/System.Console/src/System/Console.cs:line 195
   at System.ConsolePal.EnsureInitializedCore() in /_/src/libraries/System.Console/src/System/ConsolePal.Unix.cs:line 922
   at System.ConsolePal.EnsureConsoleInitialized() in /_/src/libraries/System.Console/src/System/ConsolePal.Unix.cs:line 915
   at System.ConsolePal.ControlCHandlerRegistrar.Register() in /_/src/libraries/System.Console/src/System/ConsolePal.Unix.cs:line 1451
   at System.Console.add_CancelKeyPress(ConsoleCancelEventHandler value) in /_/src/libraries/System.Console/src/System/Console.cs:line 572
   at Xunit.ConsoleClient.ConsoleRunner.EntryPoint(String[] args) in /_/src/Microsoft.DotNet.XUnitConsoleRunner/src/ConsoleRunner.cs:line 47
   at Xunit.ConsoleClient.Program.Main(String[] args) in /_/src/Microsoft.DotNet.XUnitConsoleRunner/src/Program.cs:line 16

[tmds]

CI failures are now unrelated. This is ready for review.

[stephentoub]

LGTM. Thanks for fixing it.

[ghost]

Hello @stephentoub!

Because this pull request has the auto-merge label, I will be glad to assist with helping to merge this pull request once all check-in policies pass.

p.s. you can customize the way I help with merging this pull request, such as holding this pull request until a specific person approves. Simply @mention me (@msftbot) and give me an instruction to get started! Learn more here.