Merge pull request #12875 from tschaub/raster-loop

Only trigger change event if animating a tile transition

src/ol/source/Raster.js

@@ -862,7 +862,9 @@ class RasterSource extends ImageSource {
     this.dispatchEvent(
       new RasterSourceEvent(RasterEventType.AFTEROPERATIONS, frameState, data)
     );
-    requestAnimationFrame(this.changed.bind(this));
+    if (frameState.animate) {
+      requestAnimationFrame(this.changed.bind(this));
+    }
   }
 
   disposeInternal() {