NERoomUserVideoViewListener constructor Null safety

1. netease_roomkit
2. netease_roomkit
3. NERoomUserVideoViewListener
4. NERoomUserVideoViewListener constructor

NERoomUserVideoViewListener class

1. Constructors
2. NERoomUserVideoViewListener
3. Properties
4. hashCode
5. runtimeType
6. Methods
7. noSuchMethod
8. onFirstFrameRendered
9. onFrameResolutionChanged
10. onRendererAvailable
11. toString
12. Operators
13. operator ==