fixed: cdd not working if no dbjoin element found on the page

plugins/fabrik_element/cascadingdropdown/cascadingdropdown.php

@@ -91,6 +91,26 @@ public function elementJavascript($repeatCounter)
 		return array('FbCascadingdropdown', $id, $opts);
 	}
 
+	/**
+	 * Get the class to manage the form element
+	 * if a plugin class requires to load another elements class (eg user for dbjoin then it should
+	 * call FabrikModelElement::formJavascriptClass('plugins/fabrik_element/databasejoin/databasejoin.js', true);
+	 * to ensure that the file is loaded only once
+	 *
+	 * @param   array   &$srcs   Scripts previously loaded (load order is important as we are loading via head.js
+	 * and in ie these load async. So if you this class extends another you need to insert its location in $srcs above the
+	 * current file
+	 * @param   string  $script  Script to load once class has loaded
+	 *
+	 * @return void
+	 */
+
+	public function formJavascriptClass(&$srcs, $script = '')
+	{
+		plgFabrik_Element::formJavascriptClass($srcs, 'plugins/fabrik_element/databasejoin/databasejoin.js');
+		parent::formJavascriptClass($srcs, $script);
+	}
+
 	/**
 	 * Get the field name to use as the column that contains the join's label data
 	 *