I uploaded my FreeType upgrade CL to https://chromium-review.googlesource.com/c/443346/

And tried Tools/Scripts/webkit-patch rebaseline-cl on it, but it seems the tool cannot retrieve or trigger rebaseline tryjobs on gerrit:

'Received HTTP status 404 loading "https://codereview.chromium.org/api/443346".  Retrying in 10 seconds...'

Especially for this large rebaseline CL, it would be helpful if the tool would support gerrit, since I would assume uploading large changesets is more stable on gerrit.