ClassDefinition constructor Null safety

1. macro_builder
2. definition
3. ClassDefinition
4. ClassDefinition constructor

ClassDefinition class

1. Constructors
2. ClassDefinition
3. Properties
4. constructors
5. fields
6. hashCode
7. isAbstract
8. isExternal
9. isNullable
10. methods
11. name
12. reference
13. runtimeType
14. scope
15. superclass
16. superinterfaces
17. typeArguments
18. typeParameters
19. Methods
20. isSubtype
21. noSuchMethod
22. toString
23. Operators
24. operator ==