MinMaxScaler and MaxAbsScaler have an attribute n_samples_seen which is not used to compute the statistics. For instance this is useful to have it in StandardScaler but does not bring anything in those 2 scalers.

In #11011, @jnothman proposed to deprecate this parameter which I am also in favor of.

@amueller @ogrisel Any opinion and historical reasons why this attribute is there (because the class have a partial_fit method?