diff -u b/core/lib/Drupal/Core/Extension/ModuleHandler.php b/core/lib/Drupal/Core/Extension/ModuleHandler.php
--- b/core/lib/Drupal/Core/Extension/ModuleHandler.php
+++ b/core/lib/Drupal/Core/Extension/ModuleHandler.php
@@ -1031,7 +1031,7 @@
 
     // Flush all persistent caches.
     // Any cache entry might implicitly depend on the uninstalled modules,
-    // so clear all of thethem explicitly.
+    // so clear all of them explicitly.
     $this->invokeAll('cache_flush');
     foreach (Cache::getBins() as $service_id => $cache_backend) {
       $cache_backend->deleteAll();
diff -u b/core/modules/system/src/Tests/Module/UninstallTest.php b/core/modules/system/src/Tests/Module/UninstallTest.php
--- b/core/modules/system/src/Tests/Module/UninstallTest.php
+++ b/core/modules/system/src/Tests/Module/UninstallTest.php
@@ -77,17 +77,17 @@
     }
 
     // Set a unique cache entry to be able to test whether all caches are
-    // cleared during the uninstall
-    \Drupal::cache()->set('UninstallTest', 'testUninstallPage', Cache::PERMANENT);
-    $cached = \Drupal::cache()->get('UninstallTest');
-    $this->assertEqual($cached->data, 'testUninstallPage', String::format('Cache entry found: @bin', array('@bin' => $cached->data)));
+    // cleared during the uninstall.
+    \Drupal::cache()->set('uninstall_test', 'test_uninstall_page', Cache::PERMANENT);
+    $cached = \Drupal::cache()->get('uninstall_test');
+    $this->assertEqual($cached->data, 'test_uninstall_page', String::format('Cache entry found: @bin', array('@bin' => $cached->data)));
 
     $this->drupalPostForm(NULL, NULL, t('Uninstall'));
     $this->assertText(t('The selected modules have been uninstalled.'), 'Modules status has been updated.');
     $this->assertNoRaw('<label', 'The page does not have double escaped HTML tags.');
 
     // Make sure our unique cache entry is gone.
-    $cached = \Drupal::cache()->get('UninstallTest');
+    $cached = \Drupal::cache()->get('uninstall_test');
     $this->assertFalse($cached, 'Cache entry not found');
   }
 }