diff --git a/core/modules/block/lib/Drupal/block/Tests/BlockTest.php b/core/modules/block/lib/Drupal/block/Tests/BlockTest.php
index 1a0fd00..95437fb 100644
--- a/core/modules/block/lib/Drupal/block/Tests/BlockTest.php
+++ b/core/modules/block/lib/Drupal/block/Tests/BlockTest.php
@@ -185,20 +185,17 @@ public function testBlockThemeSelector() {
    * Test block display of theme titles.
    */
   function testThemeName() {
-    \Drupal::moduleHandler()->install(array('block_test'));
+    // Enable the help block.
+    $this->drupalPlaceBlock('system_help_block', array('region' => 'help'));
     // Explicitly set the default and admin themes.
-    $theme = 'cat_mouse';
-    theme_enable(array($theme, 'seven', 'block_test_theme'));
+    $theme = 'block_test_specialchars_theme';
+    theme_enable(array($theme));
     $this->resetAll();
-
-    \Drupal::config('system.theme')
-      ->set('default', 'seven')
-      ->set('admin', 'seven')
-      ->save();
     \Drupal::service('router.builder')->rebuild();
-    $this->drupalGet('admin/appearance');
     $this->drupalGet('admin/structure/block');
     $this->assertText('<"Cat" & 'Mouse'>');
+    $this->drupalGet('admin/structure/block/list/block_test_specialchars_theme');
+    $this->assertLink('Demonstrate block regions (<"Cat" & \'Mouse\'>)');
   }
 
   /**
diff --git a/core/modules/block/tests/modules/block_test/block_test.module b/core/modules/block/tests/modules/block_test/block_test.module
index 726043c..a527ae1 100644
--- a/core/modules/block/tests/modules/block_test/block_test.module
+++ b/core/modules/block/tests/modules/block_test/block_test.module
@@ -8,15 +8,6 @@
 use Drupal\block\BlockPluginInterface;
 
 /**
- * Implements hook_system_theme_info().
- */
-function block_test_system_theme_info() {
-  $themes['block_test_theme'] = drupal_get_path('module', 'block_test') . '/themes/block_test_theme/block_test_theme.info.yml';
-  $themes['cat_mouse'] = drupal_get_path('module', 'block_test') . '/themes/cat_mouse/cat_mouse.info.yml';
-  return $themes;
-}
-
-/**
  * Implements hook_block_alter().
  */
 function block_test_block_alter(&$block_info) {
diff --git a/core/modules/block/tests/modules/block_test/themes/block_test_specialchars_theme/block_test_specialchars_theme.info.yml b/core/modules/block/tests/modules/block_test/themes/block_test_specialchars_theme/block_test_specialchars_theme.info.yml
new file mode 100644
index 0000000..5b4689e
--- /dev/null
+++ b/core/modules/block/tests/modules/block_test/themes/block_test_specialchars_theme/block_test_specialchars_theme.info.yml
@@ -0,0 +1,8 @@
+name: '<"Cat" & ''Mouse''>'
+type: theme
+description: 'Theme for testing special characters in block admin.'
+core: 8.x
+hidden: true
+regions:
+  content: Content
+  help: Help
diff --git a/core/modules/block/tests/modules/block_test/themes/cat_mouse/cat_mouse.info.yml b/core/modules/block/tests/modules/block_test/themes/cat_mouse/cat_mouse.info.yml
deleted file mode 100644
index 999f7f3..0000000
--- a/core/modules/block/tests/modules/block_test/themes/cat_mouse/cat_mouse.info.yml
+++ /dev/null
@@ -1,16 +0,0 @@
-name: '<"Cat" & ''Mouse''>'
-type: theme
-description: 'Theme for testing special characters in block admin.'
-core: 8.x
-hidden: true
-regions:
-  sidebar_first: 'Left sidebar'
-  sidebar_second: 'Right sidebar'
-  content: Content
-  header: Header
-  footer: Footer
-  highlighted: Highlighted
-  help: Help
-regions_hidden:
-  - sidebar_first
-  - sidebar_second
diff --git a/sites/README.txt b/sites/README.txt
old mode 100644
new mode 100755
diff --git a/sites/default/default.settings.php b/sites/default/default.settings.php
old mode 100644
new mode 100755
diff --git a/sites/example.sites.php b/sites/example.sites.php
old mode 100644
new mode 100755