Steps to reproduce:

1. enter the zabbix root directory
2. initialization the frontend test environment:  ant init-frontend-mysql
3. execute the test:  cd ui/test; phpunit --bootstrap=bootstrap.php selenium/dashboard/testDashboardDynamicItemWidgets.php

Result:

after the test, the temporary file 'iframe.php' under the ui directory was not deleted
Expected:
after the test, the temporary file was deleted