Fix Unix named mutex crash during some race conditions#36268

Merged

kouvel merged 2 commits intodotnet:masterfrom kouvel:NamedMutexFix

May 13, 2020

+459-91

Commits on May 12, 2020

Fix Unix named mutex crash during some race conditions
kouvel
committed
Address feedback, disable a test on Mono, slightly simplify same test (avoid two guids in name)
kouvel
committed