What is the test for contributory negligence in "willing passenger" cases?

In Eid v. Dumas, 1969 CanLII 88 (SCC), [1969] S.C.R. 668, Ritchie J. described contributory negligence in “willing passenger” cases in the following terms at 674-675: In my view, Eid [the passenger] cannot be said to have actively contributed to the accident by any negligent act of his; he was merely a passive victim and not responsible for the way the car was driven, but the doctrine of contributory negligence is not confined to cases in which the plaintiff actively participates in the result; it is equally applicable where a plaintiff fails to take reasonable steps to protect himself from the consequences of the defendant’s negligence.... I think, therefore, that the question to be determined in this case is whether, when Mr Eid allowed himself to be driven home by the respondent at 4 a.m., he showed such a disregard for his own safety as to relieve the respondent from a proportion of the responsibility for the tragic consequences which ensued.