Php-unit tests failing in nightly

[SwikritiT]

The nightly is failing with

There were 6 errors:

1) OCA\Impersonate\Tests\Controller\LogoutControllerTest::testImpersonateLogout with data set #1 ('impersonator')
TypeError: Argument 1 passed to Symfony\Component\EventDispatcher\EventDispatcher::dispatch() must be an object, string given, called in /var/www/owncloud/server/apps/impersonate/controller/logoutcontroller.php on line 103

/var/www/owncloud/server/lib/composer/symfony/event-dispatcher/EventDispatcher.php:48
/var/www/owncloud/server/apps/impersonate/controller/logoutcontroller.php:103
/var/www/owncloud/server/apps/impersonate/tests/unit/controller/LogoutControllerTest.php:147
phpvfscomposer:///var/www/owncloud/server/lib/composer/phpunit/phpunit/phpunit:106

2) OCA\Impersonate\Tests\Controller\SettingsControllerTest::testImpersonate with data set #0 ('username', 'username', 'admin')
TypeError: Argument 1 passed to Symfony\Component\EventDispatcher\EventDispatcher::dispatch() must be an object, string given, called in /var/www/owncloud/server/apps/impersonate/controller/settingscontroller.php on line 138

/var/www/owncloud/server/lib/composer/symfony/event-dispatcher/EventDispatcher.php:48
/var/www/owncloud/server/apps/impersonate/controller/settingscontroller.php:138
/var/www/owncloud/server/apps/impersonate/controller/settingscontroller.php:242
/var/www/owncloud/server/apps/impersonate/tests/unit/controller/SettingsControllerTest.php:186
phpvfscomposer:///var/www/owncloud/server/lib/composer/phpunit/phpunit/phpunit:106

3) OCA\Impersonate\Tests\Controller\SettingsControllerTest::testImpersonate with data set #1 ('Username', 'username', 'groupadmin')
TypeError: Argument 1 passed to Symfony\Component\EventDispatcher\EventDispatcher::dispatch() must be an object, string given, called in /var/www/owncloud/server/apps/impersonate/controller/settingscontroller.php on line 138

/var/www/owncloud/server/lib/composer/symfony/event-dispatcher/EventDispatcher.php:48
/var/www/owncloud/server/apps/impersonate/controller/settingscontroller.php:138
/var/www/owncloud/server/apps/impersonate/controller/settingscontroller.php:255
/var/www/owncloud/server/apps/impersonate/tests/unit/controller/SettingsControllerTest.php:221
phpvfscomposer:///var/www/owncloud/server/lib/composer/phpunit/phpunit/phpunit:106

4) OCA\Impersonate\Tests\Controller\SettingsControllerTest::testWronglyConfiguredGroupListAllowsImpersonation
TypeError: Argument 1 passed to Symfony\Component\EventDispatcher\EventDispatcher::dispatch() must be an object, string given, called in /var/www/owncloud/server/apps/impersonate/controller/settingscontroller.php on line 138

/var/www/owncloud/server/lib/composer/symfony/event-dispatcher/EventDispatcher.php:48
/var/www/owncloud/server/apps/impersonate/controller/settingscontroller.php:138
/var/www/owncloud/server/apps/impersonate/controller/settingscontroller.php:255
/var/www/owncloud/server/apps/impersonate/tests/unit/controller/SettingsControllerTest.php:377
phpvfscomposer:///var/www/owncloud/server/lib/composer/phpunit/phpunit/phpunit:106

5) OCA\Impersonate\Tests\Controller\SettingsControllerTest::testImpersonateGrantAllSubadmin
TypeError: Argument 1 passed to Symfony\Component\EventDispatcher\EventDispatcher::dispatch() must be an object, string given, called in /var/www/owncloud/server/apps/impersonate/controller/settingscontroller.php on line 138

/var/www/owncloud/server/lib/composer/symfony/event-dispatcher/EventDispatcher.php:48
/var/www/owncloud/server/apps/impersonate/controller/settingscontroller.php:138
/var/www/owncloud/server/apps/impersonate/controller/settingscontroller.php:248
/var/www/owncloud/server/apps/impersonate/tests/unit/controller/SettingsControllerTest.php:610
phpvfscomposer:///var/www/owncloud/server/lib/composer/phpunit/phpunit/phpunit:106

6) OCA\Impersonate\Tests\Controller\SettingsControllerTest::testImpersonateAppEnabledForTargetUser
TypeError: Argument 1 passed to Symfony\Component\EventDispatcher\EventDispatcher::dispatch() must be an object, string given, called in /var/www/owncloud/server/apps/impersonate/controller/settingscontroller.php on line 138

/var/www/owncloud/server/lib/composer/symfony/event-dispatcher/EventDispatcher.php:48
/var/www/owncloud/server/apps/impersonate/controller/settingscontroller.php:138
/var/www/owncloud/server/apps/impersonate/controller/settingscontroller.php:248
/var/www/owncloud/server/apps/impersonate/tests/unit/controller/SettingsControllerTest.php:720
phpvfscomposer:///var/www/owncloud/server/lib/composer/phpunit/phpunit/phpunit:106

ERRORS!
Tests: 26, Assertions: 43, Errors: 6.

Related core issue: owncloud/core#39630