Callers might need to unwrite data, after having written it. Change-Id: I2588f7b8bd282b59e5c8fb3ae9a26ea4ffe946a6 Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/79187 Reviewed-by: Adam Langley <agl@google.com> Auto-Submit: David Benjamin <davidben@google.com> Commit-Queue: David Benjamin <davidben@google.com>