Explicit void

src/ol/renderer/Map.js

@@ -6,7 +6,7 @@ import Disposable from '../Disposable.js';
 import {listen, unlistenByKey} from '../events.js';
 import EventType from '../events/EventType.js';
 import {getWidth} from '../extent.js';
-import {TRUE, UNDEFINED} from '../functions.js';
+import {TRUE, VOID} from '../functions.js';
 import {visibleAtResolution} from '../layer/Layer.js';
 import {shared as iconImageCache} from '../style/IconImageCache.js';
 import {compose as composeTransform, invert as invertTransform, setFromArray as transformSetFromArray} from '../transform.js';
@@ -329,7 +329,7 @@ function expireIconCache(map, frameState) {
  * Render.
  * @param {?module:ol/PluggableMap~FrameState} frameState Frame state.
  */
-MapRenderer.prototype.renderFrame = UNDEFINED;
+MapRenderer.prototype.renderFrame = VOID;
 
 
 /**