Make the warning error, and restore previous props so we attempt to run#15078

nohwnd merged 5 commits intomicrosoft:rel/17.14microsoft/vstest:rel/17.14from

nohwnd:error-on-unsupported-tfms-and-add-nativenohwnd/vstest:error-on-unsupported-tfms-and-add-nativeCopy head branch name to clipboard