Fix git conflict.
corrects fetch_cart urls
Fixes #5325
removes window.location.origin

isn't compatible with Internet Explorer

Fixes #5323
Revert "Only cancel cancellable shipments."

This reverts commit a1daea003802c1bd71ad9db4540ecd29c45283d1.
Dont create product if master variant invalid.
[Fixes #5306]
Fixes #5330