Issue #1893818 by Berdir, tim.plunkett: Fixed Plugin discovery caches of...

Issue #1893818 by Berdir, tim.plunkett: Fixed Plugin discovery caches of blocks are not cleared for all languages.

core/modules/aggregator/lib/Drupal/aggregator/Tests/AggregatorLanguageBlockTest.php

@@ -80,7 +80,7 @@ public function testBlockLinks() {
     foreach ($this->langcodes as $langcode) {
       $this->drupalGet('admin/structure/block', array('language' => $langcode));
       $this->clickLink(t('Add block'));
-      $this->assertText($feed->title);
+      $this->assertText($feed->label());
     }
   }
 }