Returns the hash of the per-user rendered toolbar subtrees.
function _toolbar_get_subtree_hash() {
global $user;
$cid = $user->uid . ':' . language(Language::TYPE_INTERFACE)->langcode;
if ($cache = cache('toolbar')
->get($cid)) {
$hash = $cache->data;
}
else {
$subtrees = toolbar_get_rendered_subtrees();
$hash = Crypt::hashBase64(serialize($subtrees));
cache('toolbar')
->set($cid, $hash);
}
return $hash;
}