Android.OS.FileUriExposedException: <Timeout exceeded getting exception details> Resolvido

Para quem estiver com esse problema eu resolvi com esse tutorial:

https://forums.xamarin.com/discussion/97273/launch-camera-activity-with-saving-file-in-external-storage-crashes-the-app

Basicamente você pode trocar o método OnCreate por esse:

protected override async void OnCreate(Bundle savedInstanceState)
        {
            TabLayoutResource = Resource.Layout.Tabbar;
            ToolbarResource = Resource.Layout.Toolbar;

            StrictMode.VmPolicy.Builder builder = new StrictMode.VmPolicy.Builder();
            StrictMode.SetVmPolicy(builder.Build());
            base.OnCreate(savedInstanceState);

            global::Xamarin.Forms.Forms.Init(this, savedInstanceState);
            LoadApplication(new TestDrive.App());
        }