有没有办法将`Exec`作为依赖工件？

So, here is my dilemma. I am building with gradle, and need to generate some protobuf classes. I know that there is a plugin for that, but it only works with gradle 2.12+, and that makes my build more than twice slower than the one I am using (2.8), so I don't want to upgrade. So, here is my dilemma. I am building with grad