ObjectHasSelf should allow ObjectPropertyExpression

[althonos]

ObjectHasSelf is defined in the grammar:

ObjectHasSelf := 'ObjectHasSelf' '(' ObjectPropertyExpression ')'

but in the code it is only ObjectHasSelf(ObjectProperty).

(Also, it feels weird that this one is the only other tuple variant with Class while all the other are structs variants, it's not that elegant to mix both styles IMO).

[phillord]

Hopefully, I have fixed this now (the test for ObjectHasSelf was balked anyway, so have found out something useful). Will discuss the "also" in the other issue, since it's another issue:-)