Issue #2205157 by jibran, rteijeiro | sun: Convert locale.admin.css into a library.

core/modules/locale/lib/Drupal/locale/Form/TranslateEditForm.php

@@ -34,10 +34,6 @@ public function buildForm(array $form, array &$form_state) {
 
     $langname = isset($langcode) ? $languages[$langcode]->name : "- None -";
 
-    $path = drupal_get_path('module', 'locale');
-    $form['#attached']['css'] = array(
-      $path . '/css/locale.admin.css',
-    );
     $form['#attached']['library'][] = 'locale/drupal.locale.admin';
 
     $form['langcode'] = array(

core/modules/locale/lib/Drupal/locale/Form/TranslateFilterForm.php

@@ -26,9 +26,7 @@ public function buildForm(array $form, array &$form_state) {
     $filters = $this->translateFilters();
     $filter_values = $this->translateFilterValues();
 
-    $form['#attached']['css'] = array(
-      drupal_get_path('module', 'locale') . '/css/locale.admin.css',
-    );
+    $form['#attached']['library'][] = 'locale/drupal.locale.admin';
 
     $form['filters'] = array(
       '#type' => 'details',

core/modules/locale/locale.libraries.yml

@@ -2,6 +2,9 @@ drupal.locale.admin:
   version: VERSION
   js:
     locale.admin.js: {}
+  css:
+    component:
+      css/locale.admin.css: {}
   dependencies:
     - core/jquery
     - core/drupal

core/modules/locale/locale.pages.inc

@@ -162,7 +162,6 @@ function locale_translation_status_form($form, &$form_state) {
   );
 
   $form['#attached']['library'][] = 'locale/drupal.locale.admin';
-  $form['#attached']['css'] = array(drupal_get_path('module', 'locale') . '/css/locale.admin.css');
 
   $form['actions'] = array('#type' => 'actions');
   if ($languages_update) {