Side effect of JIRA-3731
Generics are now being added to ClassNode objects created using the ClassHelper object. The AstBuilder is implemented using this ClassHelper. The result is that ClassNodes created through the Specification have generics information added to them by default, which they should not. The fix is to use ClassHelper#makeWithoutCaching(Class, false) as an API rather than ClassHelper#make(Class).
The existing Spec test should be updated to reveal where we are using this API. Then the spec can be changed to use it. Should be simple.