[main] Source code updates from dotnet/dotnet#495

mmitche merged 2 commits intomaindotnet/source-build-externals:mainfrom

darc-main-4ff38167-6e63-4a8b-b100-cab05518adb8dotnet/source-build-externals:darc-main-4ff38167-6e63-4a8b-b100-cab05518adb8Copy head branch name to clipboard