PlacesManager constructor Null safety

1. baguette
2. PlacesManager
3. PlacesManager
4. PlacesManager constructor

PlacesManager class

1. Constructors
2. PlacesManager
3. Properties
4. hashCode
5. runtimeType
6. Methods
7. addPlugin
8. cleanPlugins
9. getPlugin
10. noSuchMethod
11. open
12. removePlugin
13. toString
14. Operators
15. operator ==