Check that non-installed languages are not considered.
function testUrlRewritingEdgeCases() {
// Check URL rewriting with a non-installed language.
$non_existing = language_default();
$non_existing->langcode = $this
->randomName();
$this
->checkUrl($non_existing, 'Path language is ignored if language is not installed.', 'URL language negotiation does not work with non-installed languages');
}