diff --git a/core/modules/system/src/Tests/System/ThemeTest.php b/core/modules/system/src/Tests/System/ThemeTest.php
index 667c97a..bf94a8e 100644
--- a/core/modules/system/src/Tests/System/ThemeTest.php
+++ b/core/modules/system/src/Tests/System/ThemeTest.php
@@ -55,7 +55,7 @@ function testThemeSettings() {
     $file = current($this->drupalGetTestFiles('image'));
     $file_relative = strtr($file->uri, array('public:/' => PublicStream::basePath()));
     $default_theme_path = 'core/themes/classy';
-
+    global $base_url;
     $supported_paths = array(
       // Raw stream wrapper URI.
       $file->uri => array(
@@ -82,6 +82,11 @@ function testThemeSettings() {
         'form' => $default_theme_path . '/logo.svg',
         'src' => base_path() . $default_theme_path . '/logo.svg',
       ),
+      // Schema-less urls.
+      substr($base_url, strpos($base_url, '//')) . '/' . $default_theme_path . '/logo.svg' => [
+        'form' => substr($base_url, strpos($base_url, '//')) . '/' . $default_theme_path . '/logo.svg',
+        'src' => substr($base_url, strpos($base_url, '//')) . '/' . $default_theme_path . '/logo.svg',
+      ],
     );
     foreach ($supported_paths as $input => $expected) {
       $edit = array(
@@ -151,6 +156,7 @@ function testThemeSettings() {
       'core/misc/whatever.png',
       // Semi-absolute path to arbitrary non-existing file.
       '/core/misc/whatever.png',
+      '//core/misc/whatever.png',
       // Absolute paths to any local file (even if it exists).
       drupal_realpath($file->uri),
     );