In this case, they plan to transfer user data into another division of their company. They have bought WhatsApp LLC, with cash and shares in hand, and got (among other things) user data in return. This is a pretty clear case of selling user data of such a company, isn't it? (Note that GP never claimed that Facebook itself sold any data just that they exploit data commercially - they have given third parties extensive access to user data in the past though)

Anyway, these discussions on the technicality of the term "selling data" vs "selling access to users using data" is just means to deflect from the real problem. It doesn't get away by rephrasing.