order of returned probabilites unclear for cross_val_predict with method=predict_proba #7863
Description
Cross_val_predict has a new method parameter which is typically set to "predict_proba" to return probabilities for each class.
However the order of the classes returned is unclear. Either self.classes_ needs to be set; or the results need to be returned in a predictable order. Otherwise we have a list of probabilities for each class but no way to know which column relates to which class.