review feedback

src/core_plugins/region_map/public/choropleth_layer.js

@@ -211,8 +211,7 @@ function makeChoroplethStyler(data, colorramp, joinField) {
   const { min, max } = getMinMax(data);
   const outstandingFeatures = data.slice();
 
-
-  const joinedShapes = [];
+  const boundsOfAllFeatures = new L.LatLngBounds();
   return {
     getLeafletStyleFunction: function (geojsonFeature) {
       let lastIndex = -1;
@@ -226,7 +225,10 @@ function makeChoroplethStyler(data, colorramp, joinField) {
       }
 
       outstandingFeatures.splice(lastIndex, 1);
-      joinedShapes.push(geojsonFeature);
+
+      const boundsOfFeature = L.geoJson(geojsonFeature).getBounds();
+      boundsOfAllFeatures.extend(boundsOfFeature);
+
       return {
         fillColor: getChoroplethColor(match.value, min, max, colorramp),
         weight: 2,
@@ -243,19 +245,7 @@ function makeChoroplethStyler(data, colorramp, joinField) {
       return outstandingFeatures.map((bucket) => bucket.term);
     },
     getLeafletBounds: function () {
-
-      if (!joinedShapes.length) {
-        return null;
-      }
-
-      const bounds = L.geoJson(joinedShapes[0]).getBounds();
-      for (let i = 1; i <  joinedShapes.length; i++) {
-        const otherBounds = L.geoJson(joinedShapes[i]).getBounds();
-        bounds.extend(otherBounds);
-      }
-      return bounds;
-
-
+      return boundsOfAllFeatures.isValid() ?  boundsOfAllFeatures : null;
     }
   };