Add an explanatory comment on Block::make multi-statement variant.
Add an explanatory comment on Block::make multi-statement variant.


Former-commit-id: e4dbf458d346bceeb989d2e0f1a36db4093ab7f2
Trass3r/Halide,darkbuck/Halide,darkbuck/Halide,darkbuck/Halide,darkbuck/Halide,darkbuck/Halide,Trass3r/Halide,Trass3r/Halide,Trass3r/Halide,Trass3r/Halide,Trass3r/Halide,darkbuck/Halide,Trass3r/Halide,darkbuck/Halide