Call custom ordering functions when opening the menu with an empty input

This is useful in cases one want to suggest items when the input is
focused, before any input has been written. In such a case we want to
call processListItems to sort the suggested items.

src/SimpleAutocomplete.svelte

@@ -496,7 +496,7 @@
     return numberOfMatches(obj2, searchWords) - numberOfMatches(obj1, searchWords)
   }
 
-  function processListItems(textFiltered) {
+  function processListItems(textFiltered="") {
     // cleans, filters, orders, and highlights the list items
     prepareListItems()
 
@@ -871,7 +871,7 @@
     if (searchFunction && !listItems.length) {
       search()
     } else if (!text) {
-      filteredListItems = listItems
+      processListItems()
     }
 
     open()