Drop [TreatNullAs=EmptyString] from URL interface attributes to match the specification: https://url.spec.whatwg.org/#api Firefox and Chrome both already follow the specification and convert null to the "null" string.
Created attachment 272724 [details] Patch
Comment on attachment 272724 [details] Patch This seems like the kind of behavior that WebKit-specific content that has never been used with another web engine might rely on. Eventually it will become too risky to make this kind of change unless we have a lot of time to test things like iOS apps before Apple puts out a release with the change in it.
Comment on attachment 272724 [details] Patch Clearing flags on attachment: 272724 Committed r197507: <http://trac.webkit.org/changeset/197507>
All reviewed patches have been landed. Closing bug.