Pass destination extent to avoid garbage generation

src/ol/VectorImageTile.js

@@ -97,7 +97,7 @@ const VectorImageTile = function(tileCoord, state, sourceRevision, format,
         sourceTileGrid.getTileCoordExtent(sourceTileCoord));
       const sourceExtent = sourceTileGrid.getExtent();
       if (sourceExtent) {
-        sharedExtent = getIntersection(sharedExtent, sourceExtent);
+        sharedExtent = getIntersection(sharedExtent, sourceExtent, sharedExtent);
       }
       if (getWidth(sharedExtent) / resolution >= 0.5 &&
           getHeight(sharedExtent) / resolution >= 0.5) {

src/ol/extent.js

@@ -593,6 +593,8 @@ export function getIntersection(extent1, extent2, opt_extent) {
     } else {
       intersection[3] = extent2[3];
     }
+  } else {
+    createOrUpdateEmpty(intersection);
   }
   return intersection;
 }