Given a protocol with an optional property like: ``` protocol MyProtocol { var myProperty: String? { get } } ``` The following non-optional stubbed value is generated: ``` var invokedMyPropertyGetter = false var invokedMyPropertyGetterCount = 0 var stubbedMyProperty: String! var myProperty: String? { invokedMyPropertyGetter = true invokedMyPropertyGetterCount += 1 return stubbedMyProperty } ``` Would it be possible for optional properties to have optional stubbed values?