Well safe to say the feature did not make its way onto the phone and the good news is that if you wanted it, XDA developer qwerp_ has managed to come up with a solution that does not require users to root their phone. However it does require users to have an unlocked Nexus 6 bootloader, which to be fair is a little easier to achieve than root.
It will also require users to replace one of the files in their phone with a modified version as compiled by the developer. So if you’d like to get your hands on the tweak you can do so by heading on over to the XDA Developer forums for the download and the details. Previously there was such a feature made available to Nexus 6 owners.
However it required them to root their devices, which some users might not feel too comfortable doing, so hopefully this will be an easier option. There are plenty of tutorials out there on how to unlock your Nexus 6’s bootloader so those are worth checking out if you’re unsure about the process or what tools you will need.