[master] Fix bug where generic may occur in return type. (fixes phildawes/racer#575)
[master] Fix bug where generic may occur in return type. (fixes phildawes/racer#575)

birkenfeld/racer,hotpxl/racer,sliz1/racer,racer-rust/racer,phildawes/racer,alkama/racer,pmarcelll/racer