Json::decode changed in drupal8

--- bootstrap/theme/settings.inc. 2014-07-19 02:31:12.276236136 +0000
+++ bootstrap/theme/settings.inc 2014-07-19 02:31:24.478721449 +0000
@@ -673,7 +673,7 @@
$bootswatch_themes = array();
// Expected result.
$data = $response->getBody();
- if (($api = drupal_json_decode($data)) && is_array($api) && !empty($api['themes'])) {
+ if (($api = json_decode($data)) && is_array($api) && !empty($api['themes'])) {
foreach ($api['themes'] as $bootswatch_theme) {
$bootswatch_themes[strtolower($bootswatch_theme['name'])] = $bootswatch_theme['name'];
}