MDL-45753 events: Fix event context

my/tests/events_test.php

@@ -61,7 +61,7 @@ public function test_dashboard_viewed() {
         $user = $this->user;
         // Trigger an event: dashboard viewed.
         $eventparams = array(
-            'context' => $context = context_system::instance()
+            'context' => $context = context_user::instance($user->id)
         );
 
         $event = \core\event\dashboard_viewed::create($eventparams);