Precision issue with date parsing in ActiveRecord

Hello all,

I just recently opened supplied a patch for ticket #4498 (https://
precision-when-deserializing-timestamps-from-postgresql). In short,
the current microsecond calculation converts a rational to a float,
then to an integer, occasionally causing rounding error. I've
supplied a patch against 2-3-stable (should also apply cleanly to
master) that converts directly from rational to integer.

What's the process to get this patch considered for the next release?