NERtcChannelMediaRelayState constructor Null safety

1. nertc
2. nertc
3. NERtcChannelMediaRelayState
4. NERtcChannelMediaRelayState constructor

NERtcChannelMediaRelayState class

1. Constructors
2. NERtcChannelMediaRelayState
3. Properties
4. hashCode
5. runtimeType
6. Methods
7. noSuchMethod
8. toString
9. Operators
10. operator ==
11. Constants
12. connecting
13. failure
14. idle
15. running