title: Positioning GMSMapView to show multiple annotations at once
body: <p>My question is quite similar to <a href="https://stackoverflow.com/questions/1336370/positioning-mkmapview-to-show-multiple-annotations-at-once">this, except MKMapView.</a>
  How can I do the same process(resize the map to fit all annotations/markers on screen at once) with Google Maps?
  As I understand I have to convert MKCoordinateRegion to GMSProjection, is my way right?</p>