VisitorGroupRole.GetRepository(); obsolete

Hi.

I'm looking at some documentation regarding Improve testability and support for rapid releases without breaking changes: http://world.episerver.com/documentation/Release-Notes/ReleaseNote/?releaseNoteId=CMS-3446

When using 

VisitorGroupRole.GetRepository();

It says that I should use IVisitorGroupRoleRepository instead. However, this interface doesn't expose a GetAll method, which we are using.

I've seen a List function in IVisitorGroupRepository, but is this the same as the old function? Also, what is the difference between a visitor group role and a visitor group?