This was probably the worst offender of them all as read_bytes is the wrong
abstraction to begin with. Note this is a slight change in how processing a
record works. Rather than reading one fragment at a time, we process all
fragments in a record and return. The intent here is so that all records are
processed atomically since the connection eventually will not be able to retain
a buffer holding the record.
This loses a ton of (though not quite all yet) those a2b macros.
Change-Id: Ibe4bbcc33c496328de08d272457d2282c411b38b
Reviewed-on: https://boringssl-review.googlesource.com/8176
Reviewed-by: David Benjamin <davidben@google.com>
c660417bd7