BMFMapSearchVersion constructor Null safety

1. flutter_baidu_mapapi_search
2. flutter_baidu_mapapi_search
3. BMFMapSearchVersion
4. BMFMapSearchVersion constructor

BMFMapSearchVersion class

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