Don't modify return type of method

src/ol/layer/tilelayer.js

@@ -18,9 +18,8 @@ goog.inherits(ol.layer.TileLayer, ol.layer.Layer);
 
 
 /**
- * @inheritDoc
  * @return {ol.TileSource} Source.
  */
-ol.layer.TileLayer.prototype.getSource = function() {
+ol.layer.TileLayer.prototype.getTileSource = function() {
-  return /** @type {ol.TileSource} */ goog.base(this, 'getSource');
+  return /** @type {ol.TileSource} */ this.getSource();
 };

src/ol/renderer/dom/tilelayer.js

@@ -74,7 +74,7 @@ ol.renderer.dom.TileLayer.prototype.getLayer = function() {
  */
 ol.renderer.dom.TileLayer.prototype.getTileOffset_ = function(z, resolution) {
   var tileLayer = this.getLayer();
-  var tileSource = tileLayer.getSource();
+  var tileSource = tileLayer.getTileSource();
   var tileGrid = tileSource.getTileGrid();
   var tileOrigin = tileGrid.getOrigin(z);
   var offset = new ol.Coordinate(
@@ -167,7 +167,7 @@ ol.renderer.dom.TileLayer.prototype.render = function() {
   var resolutionChanged = (mapResolution !== this.renderedMapResolution_);
 
   var tileLayer = this.getLayer();
-  var tileSource = tileLayer.getSource();
+  var tileSource = tileLayer.getTileSource();
   var tileGrid = tileSource.getTileGrid();
 
   // z represents the "best" resolution

src/ol/renderer/webgl/tilelayer.js

@@ -316,7 +316,7 @@ ol.renderer.webgl.TileLayer.prototype.render = function() {
   var mapRotation = map.getRotation();
 
   var tileLayer = this.getLayer();
-  var tileSource = tileLayer.getSource();
+  var tileSource = tileLayer.getTileSource();
   var tileGrid = tileSource.getTileGrid();
   var z = tileGrid.getZForResolution(mapResolution);
   var tileResolution = tileGrid.getResolution(z);