only wire up zoomanim listener with _fetchTilemap for "Imagery" basemap; added zoomanim listener teardown when "Imagery" basemap layer is removed
only wire up zoomanim listener with _fetchTilemap for "Imagery" basemap; added zoomanim listener teardown when "Imagery" basemap layer is removed

Esri/esri-leaflet,Esri/esri-leaflet,Esri/esri-leaflet