SpeechPackageSyncEndpointHelper constructor Null safety

1. irte_engine
2. speech_pack_sync_endpoint_helper
3. SpeechPackageSyncEndpointHelper
4. SpeechPackageSyncEndpointHelper constructor

SpeechPackageSyncEndpointHelper class

1. Constructors
2. SpeechPackageSyncEndpointHelper
3. Properties
4. hashCode
5. runtimeType
6. Methods
7. noSuchMethod
8. toString
9. Operators
10. operator ==
11. Static methods
12. restEndpoint