title: Google Maps fill full screen. How to fill it to half screen?
body: <p>I use the next code:</p>
  
  <pre><code>var camera = GMSCameraPosition.cameraWithLatitude(40.378259,
          longitude: 49.875059, zoom: 16)
      var mapView = GMSMapView.mapWithFrame(CGRectZero, camera: camera)
      mapView.myLocationEnabled = true
      self.view = mapView
  
      var marker = GMSMarker()
      marker.position = CLLocationCoordinate2DMake(40.378259, 49.875059)
      marker.map = mapView
  </code></pre>
  
  <p>and I use constraints, but it doesn't helps me. My map fills full screen, even if I do the next:</p>
  
  <pre><code>var mapView = GMSMapView.mapWithFrame(CGRectMake(0, 0, 100, 100), camera: camera)
  </code></pre>
  
  <p>Why it doesn't work? How can I fix it? I connect it by Podfile</p>