ExpandedControlsProgressController constructor Null safety

1. flutter_cast_framework
2. widgets
3. ExpandedControlsProgressController
4. ExpandedControlsProgressController constructor

ExpandedControlsProgressController class

1. Constructors
2. ExpandedControlsProgressController
3. Properties
4. duration
5. hashCode
6. hasListeners
7. progress
8. runtimeType
9. Methods
10. addListener
11. dispose
12. noSuchMethod
13. notifyListeners
14. removeListener
15. toString
16. updateProgress
17. Operators
18. operator ==