ApplicationMessageHub constructor Null safety

1. conduit_core
2. conduit
3. ApplicationMessageHub
4. ApplicationMessageHub constructor

ApplicationMessageHub class

1. Constructors
2. ApplicationMessageHub
3. Properties
4. first
5. hashCode
6. isBroadcast
7. isEmpty
8. last
9. length
10. runtimeType
11. single
12. Methods
13. add
14. any
15. asBroadcastStream
16. asyncExpand
17. asyncMap
18. cast
19. close
20. contains
21. distinct
22. drain
23. elementAt
24. every
25. expand
26. firstWhere
27. fold
28. forEach
29. handleError
30. join
31. lastWhere
32. listen
33. map
34. noSuchMethod
35. pipe
36. reduce
37. singleWhere
38. skip
39. skipWhile
40. take
41. takeWhile
42. timeout
43. toList
44. toSet
45. toString
46. transform
47. where
48. Operators
49. operator ==