SortedSet and ReadOnlyCollection<T> are not supported

[gkronber]

I tried to serialize a type with a field of type IReadOnlyList<...>.

The types in System.Collections.Generic should be rechecked to make sure we have registered all the required types.

[gkronber]

Same for SortedSet

[abeham]

It seems the two types explicitly mentioned in this issue are supported. IReadOnlyList seems supported (as of 57191a5) and SortedSet is supported (as of 91470f2). Can this issue be closed?

[gkronber]

Indeed IReadOnlyList<> is supported already.

A transformer that handles ReadonlyCollection is missing.