Sets up Drupal unit test environment.
Overrides DrupalUnitTestBase::setUp
DrupalUnitTestBase::$modules
function setUp() {
parent::setUp();
config_install_default_config('module', 'config_test');
// Installing config_test's default configuration pollutes the global
// variable being used for recording hook invocations by this test already,
// so it has to be cleared out manually.
unset($GLOBALS['hook_config_test']);
}