BMFCalculateUtils constructor Null safety

1. flutter_baidu_mapapi_utils
2. flutter_baidu_mapapi_utils
3. BMFCalculateUtils
4. BMFCalculateUtils constructor

BMFCalculateUtils class

1. Constructors
2. BMFCalculateUtils
3. Properties
4. hashCode
5. runtimeType
6. Methods
7. noSuchMethod
8. toString
9. Operators
10. operator ==
11. Static methods
12. areaBetweenCoordinates
13. calculatePolygonArea
14. circleContainsCoordinate
15. coordConvert
16. getDirectionFromCoords
17. getLocationDistance
18. getNearestPointToLine
19. getPointToTheVerticalFootOfLine
20. polygonContainsCoordinate