Automated test tool and EpiServer personalization

Description

Step to reproduce

1. Set up a website with a block area.
2. Install the Episerver visitor group criterion pack.
3. Create a visitor group with the criterion "OS & Browser".
4. Create a console app containing:

WebClient client = new WebClient(); 
var content = client.DownloadString("URL_TO_WEBSITE_WITH_PERSONALIZED_BLOCK");

5. Get an exception.