DeclarationType constructor Null safety

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

DeclarationType class

1. Constructors
2. DeclarationType
3. Properties
4. hashCode
5. isAbstract
6. isExternal
7. name
8. runtimeType
9. Methods
10. noSuchMethod
11. toString
12. Operators
13. operator ==