Log how often DTLS negotiation failed because of incompatible ciphersuites.

webrtc/p2p/base/dtlstransportchannel.cc

 /*
  *  Copyright 2011 The WebRTC Project Authors. All rights reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
@@ skipping 262 matching lines @@
     return false;
   }
 
   downward_ = downward;
 
   dtls_->SetIdentity(local_certificate_->identity()->GetReference());
   dtls_->SetMode(rtc::SSL_MODE_DTLS);
   dtls_->SetMaxProtocolVersion(ssl_max_version_);
   dtls_->SetServerRole(ssl_role_);
   dtls_->SignalEvent.connect(this, &DtlsTransportChannelWrapper::OnDtlsEvent);
+  dtls_->SignalSSLHandshakeError.connect(
+      this, &DtlsTransportChannelWrapper::OnDtlsHandshakeError);
   if (!dtls_->SetPeerCertificateDigest(
           remote_fingerprint_algorithm_,
           reinterpret_cast<unsigned char*>(remote_fingerprint_value_.data()),
           remote_fingerprint_value_.size())) {
     LOG_J(LS_ERROR, this) << "Couldn't set DTLS certificate digest.";
     return false;
   }
 
   // Set up DTLS-SRTP, if it's been enabled.
   if (!srtp_ciphers_.empty()) {
@@ skipping 376 matching lines @@
   SignalSelectedCandidatePairChanged(this, selected_candidate_pair,
                                      last_sent_packet_id, ready_to_send);
 }
 
 void DtlsTransportChannelWrapper::OnChannelStateChanged(
     TransportChannelImpl* channel) {
   ASSERT(channel == channel_);
   SignalStateChanged(this);
 }
 
+void DtlsTransportChannelWrapper::OnDtlsHandshakeError(
+    rtc::SSLHandshakeError error) {
+  SignalDtlsHandshakeError(error);
+}
+
 }  // namespace cricket