cleaning up no longer needed ui helper methods

ui/src/components/base/ObjectSelect.svelte

@@ -24,9 +24,8 @@
         newKeyOfSelected = CommonHelper.toArray(newKeyOfSelected, true);
 
         let newSelected = [];
-        let allItems = getFlattenItems();
 
-        for (let item of allItems) {
+        for (let item of items) {
             if (CommonHelper.inArray(newKeyOfSelected, item[selectionKey])) {
                 newSelected.push(item);
             }
@@ -48,20 +47,6 @@
 
         keyOfSelected = multiple ? extractedKeys : extractedKeys[0];
     }
-
-    function getFlattenItems() {
-        if (!CommonHelper.isObjectArrayWithKeys(items, ["group", "items"])) {
-            return items; // already flatten
-        }
-
-        // extract items from groups
-        let result = [];
-        for (const group of items) {
-            result = result.concat(group.items);
-        }
-
-        return result;
-    }
 </script>
 
 <Select bind:selected {items} {multiple} {labelComponent} {optionComponent} on:show on:hide {...$$restProps}>