title: Issue with flutter and google maps widgets
body: <p>I'm really novice in flutter and i encounter an issue with google maps widget. I tried to follow the tutorial of medium: <a href="https://medium.com/flutter-io/google-maps-and-flutter-cfb330f9a245" rel="nofollow noreferrer">https://medium.com/flutter-io/google-maps-and-flutter-cfb330f9a245</a></p>
  
  <p>Unfortunately, when i'm running the app i have a blank image.
  <strong>Screenshot of the app</strong></p>
  
  <p><a href="https://i.stack.imgur.com/t8gxH.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/t8gxH.png" alt="enter image description here"></a></p>
  
  <p>Does somebody have ever encountered this problem ? Do you have a suggestion in which direction i can try to investigate?</p>