Remove drupal_set_title in field_ui module controllers

Well, we don't want check_plain here, so we're good. I guess if we need it, we'll have to call check_plain() again.

Committed/pushed to 8.x, thanks!

+++ b/core/modules/field_ui/lib/Drupal/field_ui/Form/FieldEditForm.php
@@ -92,8 +92,6 @@ public function buildForm(array $form, array &$form_state, FieldInstanceInterfac
-    drupal_set_title($this->instance->label());
-

Pretty sure this change was wrong. I.e. the title needs to be added back somewhere else. This currently only works because the hook_menu() menu item has a 'title' and if '#title' is not set and the title resolver doesn't return anything either, drupal_get_title() is called which checks the menu item title. I guess simply adding $form['#title'] would be the easiest.

I don't see what's wrong with it for now - there's a 'title callback' => 'entity_page_label' in hook_menu() - that's just fine no ?
Having to add '#title' everywhere just sounds plain ridiculous.

Well hook_menu() is only for menu links now. That should not be relied on for the actual page output. The fact that it currently works is only an artefact of legacy code. I'm not going to judge whether that is ridiculous or not, but that's simply how things are at the moment. Unless I'm completely missing something, needless to say.

@tstoeckler is right, we need a $form['#title'] because that hook_menu() entry that has a title callback is going away soon in #2111823: Convert field_ui / Entity local tasks to YAML definitions.

Committed/pushed to 8.x, thanks!