handle updateable displacement

src/ol/style/Icon.js

@@ -32,7 +32,7 @@ import {getUid} from '../util.js';
  * to provide the size of the image, with the `imgSize` option.
  * @property {Array<number>} [offset=[0, 0]] Offset, which, together with the size and the offset origin, define the
  * sub-rectangle to use from the original icon image.
- * @property {Array<number>} [displacement=[0,0]] Displacement the icon
+ * @property {Array<number>} [displacement=[0,0]] Displacement of the icon.
  * @property {import("./IconOrigin.js").default} [offsetOrigin='top-left'] Origin of the offset: `bottom-left`, `bottom-right`,
  * `top-left` or `top-right`.
  * @property {number} [opacity=1] Opacity of the icon.
@@ -244,10 +244,9 @@ class Icon extends ImageStyle {
    * @api
    */
   getAnchor() {
-    if (this.normalizedAnchor_) {
+    let anchor = this.normalizedAnchor_;
-      return this.normalizedAnchor_;
+    if (!anchor) {
-    }
+      anchor = this.anchor_;
-    let anchor = this.anchor_;
       const size = this.getSize();
       if (
         this.anchorXUnits_ == IconAnchorUnits.FRACTION ||
@@ -285,12 +284,10 @@ class Icon extends ImageStyle {
           anchor[1] = -anchor[1] + size[1];
         }
       }
-    const displacement = this.getDisplacement();
-    anchor[0] -= displacement[0];
-    anchor[1] += displacement[1];
-
       this.normalizedAnchor_ = anchor;
-    return this.normalizedAnchor_;
+    }
+    const displacement = this.getDisplacement();
+    return [anchor[0] - displacement[0], anchor[1] + displacement[1]];
   }
 
   /**