Fix SSLv3 version check in BoGo.

Static RSA key exchange in SSLv3 does not have a length prefix. We were
checking the ClientHello version rather than the final version.

Change-Id: I2d0e9d3b5a368a7caf8b1ca69f1631400a847f52
Reviewed-on: https://boringssl-review.googlesource.com/14314
Commit-Queue: David Benjamin <davidben@google.com>
Commit-Queue: Matt Braithwaite <mab@google.com>
Reviewed-by: Matt Braithwaite <mab@google.com>
CQ-Verified: CQ bot account: commit-bot@chromium.org <commit-bot@chromium.org>
diff --git a/ssl/test/runner/key_agreement.go b/ssl/test/runner/key_agreement.go
index 8aa9118..2a3e924 100644
--- a/ssl/test/runner/key_agreement.go
+++ b/ssl/test/runner/key_agreement.go
@@ -168,7 +168,7 @@
 		encrypted[0] = 0
 	}
 	ckx := new(clientKeyExchangeMsg)
-	if clientHello.vers != VersionSSL30 {
+	if ka.version != VersionSSL30 {
 		ckx.ciphertext = make([]byte, len(encrypted)+2)
 		ckx.ciphertext[0] = byte(len(encrypted) >> 8)
 		ckx.ciphertext[1] = byte(len(encrypted))