I am using Design Support Library version 23.4.0. I have enabled the gradle flag:
defaultConfig { vectorDrawables.useSupportLibrary = tr
To complement some of the answers here: backward-compatible support for VectorDrawables comes with a price and doesn't work in all cases.
In which cases does it work? I've made this diagram to help (valid for Support Library 23.4.0 to at least 25.1.0).