When a chain is complete and ends in a trusted root checks are also performed
on the TA and the callback notified with ok==1. For consistency do the same for
chains where the TA is not self signed.
(Imported from upstream's b07e4f2f46fc286c306353d5e362cbc22c8547fb)
Initial fork from f2d678e6e89b6508147086610e985d4e8416e867 (1.0.2 beta).
(This change contains substantial changes from the original and
effectively starts a new history.)
