File URL reparse issue

[rmisev]

URLs to test:
file:.//p
file:/.//p

I pass: file:///.//p
II pass: file:////p

It seems there is a bug in the URL serializer. When parsing first time, host is set to null, so URL serializer serializes path as it does with not special URL - in the 5.1. step it adds /. to the output. When parsing second time, host is empty, 5.1. conditions are not meet, so /. is not added, and now result is as expected.