Added specialization of select branches in the case that the values of the select are vectors, but the condition is scalar.
Added specialization of select branches in the case that the values of the select are vectors, but the condition is scalar.


Former-commit-id: c69365a87651c64dd29ce62b8e82290b8ed2bc2c
Trass3r/Halide,darkbuck/Halide,Trass3r/Halide,Trass3r/Halide,Trass3r/Halide,darkbuck/Halide,darkbuck/Halide,Trass3r/Halide,darkbuck/Halide,darkbuck/Halide,darkbuck/Halide,Trass3r/Halide,darkbuck/Halide,Trass3r/Halide