优化取消订单接口返回为nul时的提示信息

Code Review By Rock Zhang

@@ -727,7 +727,9 @@ class HomeController extends AbstractAction
         //调用取消订单接口,返回订单取消状态
         $data = OrderData::cancelOrderData($orderCode, $uid, $gender, $channel);
         //将取消状态返回至浏览器
-        if (empty($data['code']) && empty($data['message'])) {
+        if (!$data) {
+            $this->echoJson(array('message' => '取消订单失败'));
+        } else if (empty($data['code']) && empty($data['message'])) {
             $this->echoJson(array('code' => 200));
         } else {
             $this->echoJson($data);