Support aar consumption

I missed a pull request from https://github.com/ialbors which fixes aar consumption.

Basically when I implemented aar consumption I was preparing the dex phase to consume the classes from the classes.jar
But then the compile phase didn't work since it didn't know the classes.jar
So we implemented a kind of ugly solution to show the classes to the compile phase which broke the dex code I added before.


Credits goes to https://github.com/ialbors