diff --git a/core/lib/Drupal/Core/Extension/UpdateModuleHandler.php b/core/lib/Drupal/Core/Extension/UpdateModuleHandler.php
index 0ef5259..0e5a57b 100644
--- a/core/lib/Drupal/Core/Extension/UpdateModuleHandler.php
+++ b/core/lib/Drupal/Core/Extension/UpdateModuleHandler.php
@@ -41,6 +41,10 @@ public function getImplementations($hook) {
         return array('system');
       // This is called during rebuild to find testing themes.
       case 'system_theme_info':
+      // Those are needed by user_access() to check access on update.php.
+      case 'entity_info':
+      case 'entity_load':
+      case 'user_role_load':
         return array();
       // t() in system_stream_wrappers() needs this. Other schema calls aren't
       // supported.
diff --git a/core/lib/Drupal/Core/Session/UserSession.php b/core/lib/Drupal/Core/Session/UserSession.php
index 8ad14fb..1b89aa6 100644
--- a/core/lib/Drupal/Core/Session/UserSession.php
+++ b/core/lib/Drupal/Core/Session/UserSession.php
@@ -100,12 +100,7 @@ public function hasPermission($permission) {
       return TRUE;
     }
 
-    if ($rids = $this->getRoles()) {
-      $roles = \Drupal::entityManager()->getStorageController('user_role')->load($this->getRoles());
-    }
-    else {
-      $roles = array();
-    }
+    $roles = \Drupal::entityManager()->getStorageController('user_role')->load($this->getRoles());
 
     foreach ($roles as $role) {
       if ($role->hasPermission($permission)) {
diff --git a/core/modules/user/lib/Drupal/user/Plugin/Core/Entity/User.php b/core/modules/user/lib/Drupal/user/Plugin/Core/Entity/User.php
index 06fe134..e0b40d7 100644
--- a/core/modules/user/lib/Drupal/user/Plugin/Core/Entity/User.php
+++ b/core/modules/user/lib/Drupal/user/Plugin/Core/Entity/User.php
@@ -376,12 +376,7 @@ public function hasPermission($permission) {
       return TRUE;
     }
 
-    if ($rids = $this->getRoles()) {
-      $roles = \Drupal::entityManager()->getStorageController('user_role')->load($this->getRoles());
-    }
-    else {
-      $roles = array();
-    }
+    $roles = \Drupal::entityManager()->getStorageController('user_role')->load($this->getRoles());
 
     foreach ($roles as $role) {
       if ($role->hasPermission($permission)) {
diff --git a/core/modules/user/user.module b/core/modules/user/user.module
index 67978a2..77e7841 100644
--- a/core/modules/user/user.module
+++ b/core/modules/user/user.module
@@ -1777,7 +1777,6 @@ function user_role_revoke_permissions($rid, array $permissions = array()) {
     $role->revokePermission($permission);
   }
   $role->save();
-  // Clear the user access cache.
 }
 
 function user_multiple_cancel_confirm($form, &$form_state) {
diff --git a/core/tests/Drupal/Tests/Core/Session/UserSessionTest.php b/core/tests/Drupal/Tests/Core/Session/UserSessionTest.php
index dc22da1..0ce1224 100644
--- a/core/tests/Drupal/Tests/Core/Session/UserSessionTest.php
+++ b/core/tests/Drupal/Tests/Core/Session/UserSessionTest.php
@@ -91,7 +91,8 @@ protected function setUp() {
         array('last example permission', FALSE),
       )));
 
-    $role_storage = $this->getMockBuilder('Drupal\User\RoleStorageController')
+    $role_storage = $this->getMockBuilder('Drupal\user\RoleStorageController')
+      ->disableOriginalConstructor()
       ->setMethods(array('load'))
       ->getMock();
     $role_storage->expects($this->any())
@@ -148,12 +149,7 @@ public function testHasPermission($permission, array $sessions_with_access, arra
       $this->assertTrue($this->users[$name]->hasPermission($permission));
     }
     foreach ($sessions_without_access as $name) {
-      try {
-        $this->assertFalse($this->users[$name]->hasPermission($permission));
-      }
-      catch (\Exception $e) {
-        $foo = 123;
-      }
+      $this->assertFalse($this->users[$name]->hasPermission($permission));
     }
   }