Review uses of *unsafe* APIs
From the review thread:
can we please get rid of all the withUnsafe*Bytes? Swift is a memory-safe language unless you use unsafe. Especially network parsers should stay clear of using this because that brings us back straight back to the unsafe C land. If there's a concept concept that you cannot express with ByteBuffer's APIs that don't contain unsafe, please file a bug. (That is unless you have to interface with C of course where you'll need the unsafe functions).