Issue #2102449 by swentel: Remove drupal_set_title() in field_ui module controllers.

core/modules/field_ui/lib/Drupal/field_ui/Form/FieldEditForm.php

@@ -91,8 +91,6 @@ public function buildForm(array $form, array &$form_state, FieldInstanceInterfac
     $field = $this->instance->getField();
     $form['#field'] = $field;
 
-    drupal_set_title($this->instance->label());
-
     $description = '<p>' . $this->t('These settings apply to the %field field everywhere it is used. These settings impact the way that data is stored in the database and cannot be changed once data has been created.', array('%field' => $this->instance->label())) . '</p>';
 
     // Create a form structure for the field values.

core/modules/field_ui/lib/Drupal/field_ui/Form/FieldInstanceEditForm.php

@@ -69,10 +69,11 @@ public function buildForm(array $form, array &$form_state, FieldInstanceInterfac
     $field = $this->instance->getField();
     $bundles = entity_get_bundles();
 
-    drupal_set_title($this->t('%instance settings for %bundle', array(
+    $form_title = $this->t('%instance settings for %bundle', array(
       '%instance' => $this->instance->getFieldLabel(),
       '%bundle' => $bundles[$entity_type][$bundle]['label'],
-    )), PASS_THROUGH);
+    ));
+    $form['#title'] = $form_title;
 
     $form['#field'] = $field;
     // Create an arbitrary entity object (used by the 'default value' widget).