Less chance of problems should the prototype ever change. This doesn't make it any more or less a circular dependency. (It actually isn't; crypto/chacha doesn't use crypto/rand and CMakeLists.txt actually puts rand above chacha anyway.) Change-Id: Ia80289f801f76551737233f158755aac99ddd74a Reviewed-on: https://boringssl-review.googlesource.com/5262 Reviewed-by: Adam Langley <agl@google.com>