Add showSearch option to dropdown

This is a highly specific option, so we shouldn't add it to the FormField class itself

modules/backend/classes/FormField.php

@@ -548,6 +548,17 @@ class FormField
         return HtmlHelper::nameToId($id);
     }
 
+    /**
+     * Returns a raw config item value.
+     * @param  string $value
+     * @param  string $default
+     * @return mixed
+     */
+    public function getConfig($value, $default = null)
+    {
+        return array_get($this->config, $value, $default);
+    }
+
     /**
      * Returns this fields value from a supplied data set, which can be
      * an array or a model or another generic collection.

modules/backend/widgets/form/partials/_field_dropdown.htm

@@ -1,5 +1,6 @@
 <?php
     $fieldOptions = $field->options();
+    $useSearch = $field->getConfig('showSearch', true);
 ?>
 <!-- Dropdown -->
 <?php if ($this->previewMode): ?>
@@ -8,7 +9,7 @@
     <select
         id="<?= $field->getId() ?>"
         name="<?= $field->getName() ?>"
-        class="form-control custom-select"
+        class="form-control custom-select <?= $useSearch ? '' : 'select-no-search' ?>"
         <?= $field->getAttributes() ?>>
         <?php if ($field->placeholder): ?>
             <option value=""><?= e(trans($field->placeholder)) ?></option>