Splits content with Rabin Fingerprints.
Probably use the byCDChunk convenience function instead of this constructor directly. Note that Chunker will popFront the input range during construction.
Updates front to contain the position and data of the next chunk. Note that Chunker reuses the chunk buffer, so the previous contents of front.data will be overwritten.
One content-dependent chunk of bytes whose end was cut when the Rabin Fingerprint had the value stored in cut.