Can't attach Visual Studio 2017 to Unity 2017, because UnityAds

I used UnityAds since Unity 5.x verison. And now I migrate to Unity 2017, which has built-in UnityAds. So I remove all external UnityAds package parts, and now I have a problem. My project runs okay from Unity editor, but when I try to attach Visual Studio project - it throws error CS0246: The type or namespace name 'ShowResult' could not be found (are you missing a using directive or an assembly reference?) ShowResult - is enum from UnityEngine.Advertisements. What should I do? I already tried to switch off Ads in Services, then restart Unity, then switch on. No result. I am using Unity 2017.1.1p1 and Visual Studio Community 2017 Version 15.3.4