EWS is pretty aggressive about clean builds. The problem with this is that "clean" builds include deleting Tools/Scripts/libraries/autoinstalled, which is generally a bad idea because it relies off of the network and pypi for future Python invocations.
<rdar://problem/80033943>
Created attachment 432709 [details] Patch
Committed r279482 (239335@main): <https://commits.webkit.org/239335@main> All reviewed patches have been landed. Closing bug and clearing flags on attachment 432709 [details].
Committed r279486 (239338@main): <https://commits.webkit.org/239338@main>
r279486 is for Bug 227595