Replaced static with $this in phpdoc since current IDEs are finally able to handle it correctly

ActiveField.php

@@ -326,7 +326,7 @@ class ActiveField extends \yii\widgets\ActiveField
 
     /**
      * @param boolean $value whether to render a inline list
-     * @return static the field object itself
+     * @return $this the field object itself
      * Make sure you call this method before [[checkboxList()]] or [[radioList()]] to have any effect.
      */
     public function inline($value = true)