code: function(leafletScene, entityCollection) {
    if (!defined(leafletScene)) {
      throw new DeveloperError("leafletScene is required.");
    }
    if (!defined(entityCollection)) {
      throw new DeveloperError("entityCollection is required.");
    }
  
    var featureGroup = L.featureGroup().addTo(leafletScene.map);
    entityCollection.collectionChanged.addEventListener(
      LeafletGeomVisualizer.prototype._onCollectionChanged,
      this
    );
  
    this._leafletScene = leafletScene;
    this._featureGroup = featureGroup;
    this._entityCollection = entityCollection;
    this._entitiesToVisualize = new AssociativeArray();
    this._entityHash = {};
  
    this._onCollectionChanged(entityCollection, entityCollection.values, [], []);
  }
docs: NOT IMPLEMENTED Path primitive - no need identified Ellipse primitive - no need identified Ellipsoid primitive - 3d prim - no plans for this Model primitive - 3d prim - no plans for this 
  A {@link Visualizer} which maps {@link Entity#point} to Leaflet primitives.
  @alias LeafletGeomVisualizer
  @constructor
  
  @param {LeafletScene} leafletScene The Leaflet scene that the the primitives will be rendered in.
  @param {EntityCollection} entityCollection The entityCollection to visualize.