places library Null safety

Classes

GoogleMapsPlaces
https://developers.google.com/places/web-service/
MatchedSubstring
OpeningHoursDetail
OpeningHoursPeriod
OpeningHoursPeriodDate
Photo
PlaceDetails
PlacesAutocompleteResponse
PlacesDetailsResponse
Prediction
Review
StructuredFormatting
Term

Enums

PriceLevel