dirty property Null safety

1. sendbird_sdk
2. cached_data_map
3. CachedDataMap<T>
4. dirty property

CachedDataMap class

1. Constructors
2. CachedDataMap
3. Properties
4. dirty
5. hashCode
6. key
7. policy
8. primaryKey
9. runtimeType
10. Methods
11. addMap
12. addWithKey
13. copyWith
14. evict
15. getAll
16. getWithKey
17. getWithKeys
18. merge
19. noSuchMethod
20. removeAll
21. removeWithKey
22. removeWithKeys
23. toString
24. Operators
25. operator ==