void VTChanged(object sender, VisualTreeChangeEventArgs e)
{
var parentSourInfo = e.Parent == null ? null : VisualDiagnostics.GetXamlSourceInfo(e.Parent);
var childSourInfo = VisualDiagnostics.GetXamlSourceInfo(e.Child);
if (childSourInfo == null)
{
failures++;
}
if (e.Parent != null && parentSourInfo == null)
{
failures++;
}
}
