fix(dropdown): support manual removed entries

When the input of a dropdown (which holds the selected values) was changed , the change does not recognize when values are missing, which have been selected before.

Author: lubber-de

src/definitions/modules/dropdown.js

@@ -2798,19 +2798,27 @@
                         $selectedItem = settings.allowAdditions
                             ? $selectedItem || module.get.itemWithAdditions(value)
                             : $selectedItem || module.get.item(value);
-                        if (!$selectedItem) {
+                        if (!$selectedItem && value !== undefined) {
                             return false;
                         }
-                        module.debug('Setting selected menu item to', $selectedItem);
-                        if (module.is.multiple() && !keepSearchTerm) {
-                            module.remove.searchWidth();
-                        }
-                        if (module.is.single()) {
+                        if (isMultiple) {
+                            if (!keepSearchTerm) {
+                                module.remove.searchWidth();
+                            }
+                            if (settings.useLabels) {
+                                module.remove.selectedItem();
+                                if (value === undefined) {
+                                    module.remove.labels($module.find(selector.label), true);
+                                }
+                            }
+                        } else {
                             module.remove.activeItem();
                             module.remove.selectedItem();
-                        } else if (settings.useLabels) {
-                            module.remove.selectedItem();
                         }
+                        if (!$selectedItem) {
+                            return false;
+                        }
+                        module.debug('Setting selected menu item to', $selectedItem);
                         // select each item
                         $selectedItem
                             .each(function () {