ui.tools.traceback: fix use of error-in-pprint.
ui.tools.traceback: fix use of error-in-pprint.

mrjbq7/factor,factor/factor,factor/factor,tgunr/factor,mrjbq7/factor,tgunr/factor,factor/factor,mrjbq7/factor,tgunr/factor,factor/factor,tgunr/factor,mrjbq7/factor,mrjbq7/factor,factor/factor,tgunr/factor,factor/factor,mrjbq7/factor,tgunr/factor