Add a test that uses print and print_when.
Add a test that uses print and print_when.


Former-commit-id: 7f74722aafa7bbf230e2cab8a11f05acb3e7e32a
darkbuck/Halide,Trass3r/Halide,Trass3r/Halide,darkbuck/Halide,Trass3r/Halide,darkbuck/Halide,darkbuck/Halide,Trass3r/Halide,darkbuck/Halide,darkbuck/Halide,Trass3r/Halide,Trass3r/Halide,Trass3r/Halide,darkbuck/Halide