Reuse properties from ol.layer.TileProperty

src/ol/layer/vectortile.js

@@ -71,7 +71,7 @@ ol.layer.VectorTile.prototype.createRenderer = function(mapRenderer) {
  * @api
  */
 ol.layer.VectorTile.prototype.getPreload = function() {
-  return /** @type {number} */ (this.get(ol.layer.VectorTile.Property_.PRELOAD));
+  return /** @type {number} */ (this.get(ol.layer.TileProperty.PRELOAD));
 };
 
 
@@ -91,7 +91,7 @@ ol.layer.VectorTile.prototype.getRenderMode = function() {
  */
 ol.layer.VectorTile.prototype.getUseInterimTilesOnError = function() {
   return /** @type {boolean} */ (
-      this.get(ol.layer.VectorTile.Property_.USE_INTERIM_TILES_ON_ERROR));
+      this.get(ol.layer.TileProperty.USE_INTERIM_TILES_ON_ERROR));
 };
 
 
@@ -116,13 +116,3 @@ ol.layer.VectorTile.prototype.setUseInterimTilesOnError = function(useInterimTil
   this.set(
       ol.layer.TileProperty.USE_INTERIM_TILES_ON_ERROR, useInterimTilesOnError);
 };
-
-
-/**
- * @enum {string}
- * @private
- */
-ol.layer.VectorTile.Property_ = {
-  PRELOAD: 'preload',
-  USE_INTERIM_TILES_ON_ERROR: 'useInterimTilesOnError'
-};