net: fix verification merge savings calculations.

net/socket/ssl_client_socket_nss.cc

 // Copyright (c) 2010 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // This file includes code SSLClientSocketNSS::DoVerifyCertComplete() derived
 // from AuthCertificateCallback() in
 // mozilla/security/manager/ssl/src/nsNSSCallbacks.cpp.
 
 /* ***** BEGIN LICENSE BLOCK *****
  * Version: MPL 1.1/GPL 2.0/LGPL 2.1
@@ skipping 2430 matching lines @@
   start_cert_verification_time_ = base::TimeTicks::Now();
 
   if (ssl_host_info_.get() && !ssl_host_info_->state().certs.empty() &&
       predicted_cert_chain_correct_) {
     // If the SSLHostInfo had a prediction for the certificate chain of this
     // server then it will have optimistically started a verification of that
     // chain. So, if the prediction was correct, we should wait for that
     // verification to finish rather than start our own.
     net_log_.AddEvent(NetLog::TYPE_SSL_VERIFICATION_MERGED, NULL);
     UMA_HISTOGRAM_ENUMERATION("Net.SSLVerificationMerged", 1 /* true */, 2);
-    base::TimeTicks now = base::TimeTicks::Now();
+    base::TimeTicks end_time = ssl_host_info_->verification_end_time();
+    if (end_time.is_null())
+      end_time = base::TimeTicks::Now();
     UMA_HISTOGRAM_TIMES("Net.SSLVerificationMergedMsSaved",
-                        now - ssl_host_info_->verification_start_time());
+                        end_time - ssl_host_info_->verification_start_time());
     server_cert_verify_result_ = &ssl_host_info_->cert_verify_result();
     return ssl_host_info_->WaitForCertVerification(&handshake_io_callback_);
   } else {
     UMA_HISTOGRAM_ENUMERATION("Net.SSLVerificationMerged", 0 /* false */, 2);
   }
 
   int flags = 0;
   if (ssl_config_.rev_checking_enabled)
     flags |= X509Certificate::VERIFY_REV_CHECKING_ENABLED;
   if (ssl_config_.verify_ev_cert)
@@ skipping 162 matching lines @@
     case SSL_CONNECTION_VERSION_TLS1_1:
       UpdateConnectionTypeHistograms(CONNECTION_SSL_TLS1_1);
       break;
     case SSL_CONNECTION_VERSION_TLS1_2:
       UpdateConnectionTypeHistograms(CONNECTION_SSL_TLS1_2);
       break;
   };
 }
 
 }  // namespace net