“ We say this, because it is obvious on the face of the record that the court below rested its decision solely on the ground that the plaintiff, as a purchaser pendente lite for the trustee, was bound by the decree renderd against the trustee in the equity cause, and that, giving to that decree the effect which it was entitled to have as the thing adjudged, under general principles of law it operated to estop the trustee and the plaintiff, his privy, from asserting title to the property. ”