Fixed subproto access in ExistingProto.
Fixed subproto access in ExistingProto.

It used to actually call the function to see if the result was a proto, but
that was clearly a problem if the function had a side effect.  Now it checks
the subprotos info in the ClassInfo.

stevefolta/trylon,stevefolta/trylon,stevefolta/trylon,stevefolta/trylon,stevefolta/trylon