Back-compat

Author: anhskohbo

src/Concerns/CMB2_Form.php

@@ -33,6 +33,10 @@ public function mb_object_type() {
  * {@inheritdoc}
  */
 public function get_field( $field, $field_group = null, $deprecated = false ) {
+if ( $field instanceof \CMB2_Field ) {
+return $field;
+}
+
 $field = is_array( $field ) ? $field['id'] : (string) $field;
 
 // Just for back-compat.