Tests that the cookies from a previous test do not bleed into a new test.
SimpleTestBrowserTestCase::testCookies().
public function testCookieDoesNotBleed() {
// In order for this test to be effective it should always run after the
// testCookies() test.
$this
->assertTrue(self::$cookieSet, 'Tests have been executed in the expected order.');
$this
->assertEqual(count($this->cookies), 0, 'No cookies are present at the start of a new test.');
}