Add layer background

src/ol/layer/VectorTile.js

@@ -65,6 +65,8 @@ import {assign} from '../obj.js';
  * @property {import("../style/Style.js").StyleLike|null} [style] Layer style. When set to `null`, only
  * features that have their own style will be rendered. See {@link module:ol/style/Style~Style} for the default style
  * which will be used if this is not set.
+ * @property {import("./Base.js").BackgroundColor|false} [background] Background color for the layer. If not specified, no
+ * background will be rendered.
  * @property {boolean} [updateWhileAnimating=false] When set to `true`, feature batches will be
  * recreated during animations. This means that no vectors will be shown clipped, but the setting
  * will have a performance impact for large amounts of vector data. When set to `false`, batches
@@ -145,6 +147,20 @@ class VectorTileLayer extends BaseVectorLayer {
         ? options.useInterimTilesOnError
         : true
     );
+
+    /**
+     * @return {import("./Base.js").BackgroundColor} Background color.
+     * @function
+     * @api
+     */
+    this.getBackground;
+
+    /**
+     * @param {import("./Base.js").BackgroundColor} background Background color.
+     * @function
+     * @api
+     */
+    this.setBackground;
   }
 
   createRenderer() {