Issue #2405903 by Berdir, gvso: Our charset metatag is not valid HTML according to W3C validator

core/modules/system/src/Tests/Installer/InstallerTest.php

@@ -39,7 +39,7 @@ protected function setUpLanguage() {
     // Test that \Drupal\Core\Render\BareHtmlPageRenderer adds assets and
     // metatags as expected to the first page of the installer.
     $this->assertRaw('core/themes/seven/css/components/buttons.css');
-    $this->assertRaw('<meta name="charset" charset="utf-8" />');
+    $this->assertRaw('<meta charset="utf-8" />');
     parent::setUpLanguage();
   }
 }

core/modules/system/src/Tests/Page/DefaultMetatagsTest.php

@@ -22,12 +22,11 @@ class DefaultMetatagsTest extends WebTestBase {
   public function testMetaTag() {
     $this->drupalGet('');
     // Ensures that the charset metatag is on the page.
-    $result = $this->xpath('//meta[@name="charset" and @charset="utf-8"]');
+    $result = $this->xpath('//meta[@charset="utf-8"]');
     $this->assertEqual(count($result), 1);
 
     // Ensure that the charset one is the first metatag.
     $result = $this->xpath('//meta');
-    $this->assertEqual((string) $result[0]->attributes()->name, 'charset');
     $this->assertEqual((string) $result[0]->attributes()->charset, 'utf-8');
 
     // Ensure that the shortcut icon is on the page.

core/modules/system/system.module

@@ -551,7 +551,6 @@ function system_page_attachments(array &$page) {
     'system_meta_content_type' => array(
       '#tag' => 'meta',
       '#attributes' => array(
-        'name' => 'charset',
         'charset' => 'utf-8',
       ),
       // Security: This always has to be output first.