System.IO.Pipes from CoreFX (#9573)

Rework of #5448, contributes to #7143.

The anonymous pipes were tested on macOS, build was tested only on few configurations (hoping to solve some issue through Jenkins builds). Named pipe tests get stuck on macOS, but it may be unrelated Xunit issue and needs some proper debugging.

@Therzok, do you know of anything else that is missing for parallel MSBuild? Do you have some test environment for it by chance?

2 files changed, 0 insertions, 0 deletions

diff --git a/external/api-snapshot b/external/api-snapshot
-Subproject cfd5b80da4802b28fe7ca6c009752eba00b14f5
+Subproject 7732747584ef4a0a407f62aff1eb868b08161c0
diff --git a/external/corefx b/external/corefx
-Subproject 3b4d729093a14cf8805623e53e05e5acb05c78f
+Subproject 577b6a73341b11fa79484bc6bceb2cb4ca2acb9