diff -u b/core/modules/system/src/Tests/Module/InstallUninstallTest.php b/core/modules/system/src/Tests/Module/InstallUninstallTest.php
--- b/core/modules/system/src/Tests/Module/InstallUninstallTest.php
+++ b/core/modules/system/src/Tests/Module/InstallUninstallTest.php
@@ -34,7 +34,6 @@
     $this->assertEqual($this->container->get('state')->get('system_test_preuninstall_module'), 'module_test');
     $this->resetAll();
 
-    // Try to install and uninstall book, toolbar modules and its dependencies.
     $all_modules = system_rebuild_module_data();
 
     // Test help on required modules, but do not test uninstalling.
only in patch2:
unchanged:
--- a/core/modules/system/tests/modules/accept_header_routing_test/accept_header_routing_test.info.yml
+++ b/core/modules/system/tests/modules/accept_header_routing_test/accept_header_routing_test.info.yml
@@ -1,3 +1,4 @@
 name: Accept header based routing test
 core: 8.x
 type: module
+package: Testing
only in patch2:
unchanged:
--- a/core/modules/system/tests/modules/conneg_test/conneg_test.info.yml
+++ b/core/modules/system/tests/modules/conneg_test/conneg_test.info.yml
@@ -1,6 +1,6 @@
 name: Content negotiation test
 type: module
 description: 'Support testing content negotiation variations.'
-package: Core
+package: Testing
 version: VERSION
 core: 8.x