onDispose method Null safety

1. baguette
2. View
3. View<T extends ViewWidget>
4. onDispose method

View class

1. Constructors
2. View
3. Properties
4. context
5. hashCode
6. mounted
7. runtimeType
8. widget
9. Methods
10. activate
11. build
12. buildContent
13. deactivate
14. debugFillProperties
15. didChangeDependencies
16. didUpdateWidget
17. dispose
18. getViewModel
19. initState
20. noSuchMethod
21. notifyChanges
22. onCreate
23. onDispose
24. reassemble
25. setState
26. setViewModel
27. toDiagnosticsNode
28. toString
29. toStringShort
30. Operators
31. operator ==