Test non-default theme admin.
function testNonDefaultBlockAdmin() {
$admin_user = $this
->drupalCreateUser(array(
'administer blocks',
'administer themes',
));
$this
->drupalLogin($admin_user);
$new_theme = 'bartik';
theme_enable(array(
$new_theme,
));
$this
->drupalGet('admin/structure/block/list/block_plugin_ui:' . $new_theme);
$this
->assertText('Bartik(' . t('active tab') . ')', 'Tab for non-default theme found.');
}