The opaque host parser allows the empty string, contradicting opaque hosts being "non-empty ASCII string[s]" #908

What is the issue with the URL Standard?

1. The opaque host definition says "An opaque host is a non-empty ASCII string that can be used for further processing." (emphasis mine).

2. The opaque host parser currently does nothing to change or reject the empty string, thus returning the empty opaque host.

I think changing the "non-empty" in the opaque host's definition to "possibly empty" is backwards compatible? Any code using the official parser already can't assume opaque hosts are never empty.