@exportSymbol ol.FeatureOverlay
@exportProperty ol.FeatureOverlay.prototype.addFeature
@exportProperty ol.FeatureOverlay.prototype.getFeatures
@exportProperty ol.FeatureOverlay.prototype.setFeatures
@exportProperty ol.FeatureOverlay.prototype.setMap
@exportProperty ol.FeatureOverlay.prototype.setStyleFunction
@exportProperty ol.FeatureOverlay.prototype.removeFeature