Trying to set an invalid date string as a date results in Mongoid::Errors::InvalidTime (3.0.21)

Hey guys

We used 3.0.5 before, where setting an invalid string as a date resulted in Mongoid converting the string into 1st january of 1970.

Now we updated to 3.0.21 where this behavior changed: now a Mongoid::Errors::InvalidTime is thrown, and this happens before any validations kick in.

This can't be expected behavior, can it? Please take a look at it, thank you.