This was a mistake from when we added async CertificateVerify support. No test because the final state of each write state is semi-unreachable due to the buffer BIO that gets installed on each handshake. Change-Id: I0180926522113c8b1ca58b8c9c6dc37fb0dd8083 Reviewed-on: https://boringssl-review.googlesource.com/6412 Reviewed-by: Adam Langley <agl@google.com>kris/onging/CECPQ3_patch15