Google runs a program Google Made for manufacturers of accessories
According to the source, with new smartphones Pixel the search giant will present a program Made for Google. It will be a certification program for third-party accessories.
A similar program is, Apple (Apple MFi), so we can assume that Google will work in a similar way. That is, for a fee, producers will receive the company’s assistance in the development of various accessories, consisting of relevant technical documentation, assistance in component selection and technical support.
While there is a version that is basically the program will target third-party charger, but it is possible to say only after the announcement.