Sorry for the mistake. I have also tried it and i have:
Error 2 Undefined namespace. The 'using' URI refers to a namespace 'Microsoft.Advertising.Mobile.UI' that could not be found. C:\Dev\cocos\MyGame\proj.win8.1-universal\App.Shared\OpenGLESPage.xaml 8 14 MyGame.Windows
Error 3 The type 'UI:AdControl' was not found. Verify that you are not missing an assembly reference and that all referenced assemblies have been built. C:\Dev\cocos\MyGame\proj.win8.1-universal\App.Shared\OpenGLESPage.xaml 25 26 MyGame.Windows
Error 1 The name "AdControl" does not exist in the namespace "using:Microsoft.Advertising.Mobile.UI". C:\Dev\cocos\MyGame\proj.win8.1-universal\App.Shared\OpenGLESPage.xaml 25 25 MyGame.Windows
Error 4 error WMC0001: Unknown type 'AdControl' in XML namespace 'using:Microsoft.Advertising.Mobile.UI' C:\Dev\cocos\MyGame\proj.win8.1-universal\App.Shared\OpenGLESPage.xaml 25 26 MyGame.Windows