呈现多个WKInterfaceController（在页面基本导航中）会导致watchOS4顶部出现额外的黑色空间。

The application was running well before watchOS4 but in watchOS4 there is extra black space is visible on top of WKInterfaceController. This case happens in present WKInterfaceController only but seems working fine if I try to push WKInterfaceController. The application was running well before watchOS