title: Can not clear marker in Mapbox GL
body: <p>When I clear all marker I have error </p>
  
  <blockquote>
    <p>Uncaught TypeError: Cannot read property 'lng' of undefined</p>
  </blockquote>
  
  <p>My code:</p>
  
  <pre><code>var map = new mapboxgl.Map({
          container: 'map',
          style: 'mapbox://styles/mapbox/streets-v9',
      });
  
  var marker = new mapboxgl.Marker().addTo(map);
  marker.remove();
  </code></pre>