Migrate TLS 1.2 and below state machines to the new style.

Bug: 128
Change-Id: Ief3779b1c43dd34a154a0f1d2f94d0da756bc07a
Reviewed-on: https://boringssl-review.googlesource.com/19144
Reviewed-by: David Benjamin <davidben@google.com>
Commit-Queue: David Benjamin <davidben@google.com>
CQ-Verified: CQ bot account: commit-bot@chromium.org <commit-bot@chromium.org>
diff --git a/ssl/t1_lib.cc b/ssl/t1_lib.cc
index e50710a..7527a98 100644
--- a/ssl/t1_lib.cc
+++ b/ssl/t1_lib.cc
@@ -3483,7 +3483,7 @@
    * handshake hashes that we wish to record are for the original, full
    * handshake. */
   if (ssl->session != NULL) {
-    return -1;
+    return 0;
   }
 
   static_assert(
@@ -3493,7 +3493,7 @@
   size_t digest_len;
   if (!hs->transcript.GetHash(hs->new_session->original_handshake_hash,
                               &digest_len)) {
-    return -1;
+    return 0;
   }
 
   static_assert(EVP_MAX_MD_SIZE <= 0xff,