Test that cfg.blocked_domain entries are added to the output.

-- Testcase --
import adb from 'adblock-fast';
import { readfile } from 'fs';
let ti = adb._test_internals;

adb.env.load_config();
ti.set_cfg('dns', 'dnsmasq.servers');
ti.set_cfg('dnsmasq_sanity_check', false);
ti.set_cfg('dnsmasq_validity_check', false);
ti.set_cfg('heartbeat_domain', null);
ti.set_cfg('config_update_enabled', false);
ti.set_cfg('update_config_sizes', false);
ti.set_cfg('blocked_domain', 'custom-block-1.example.net custom-block-2.example.net');
ti.env.dns_set_output_values('dnsmasq.servers');
ti.append_urls();

let ok = ti.download_lists();
if (!ok) {
	print('download_lists failed\n');
} else {
	let content = readfile(ti.dns_output.file) || '';

	let customs = [
		'custom-block-1.example.net',
		'custom-block-2.example.net',
	];
	let results = [];
	for (let d in customs) {
		let found = index(content, 'server=/' + d + '/') >= 0;
		push(results, sprintf('%s: %s', d, found ? 'PRESENT' : 'MISSING'));
	}
	print(join('\n', results) + '\n');
}
-- End --

-- Expect stdout --
custom-block-1.example.net: PRESENT
custom-block-2.example.net: PRESENT
-- End --