Added DtlsCertificate, a ref counted object owning an SSLIdentity

talk/app/webrtc/statscollector.cc

Index: talk/app/webrtc/statscollector.cc
diff --git a/talk/app/webrtc/statscollector.cc b/talk/app/webrtc/statscollector.cc
index ad64639eb93a18f04295499712163f49331080af..dac312a90b8a5190865eae903f2040af37b5213c 100644
--- a/talk/app/webrtc/statscollector.cc
+++ b/talk/app/webrtc/statscollector.cc
@@ -700,9 +700,10 @@ void StatsCollector::ExtractSessionInfo() {
 
     cricket::Transport* transport =
         session_->GetTransport(transport_iter.second.content_name);
-    rtc::scoped_ptr<rtc::SSLIdentity> identity;
-    if (transport && transport->GetIdentity(identity.accept())) {
-      StatsReport* r = AddCertificateReports(&(identity->certificate()));
+    rtc::scoped_refptr<webrtc::DtlsCertificate> dtlscert;
+    if (transport && transport->GetCertificate(&dtlscert)) {
+      StatsReport* r = AddCertificateReports(
+          &(dtlscert->identity()->certificate()));

[Henrik Grunell WebRTC, 2015/08/12 14:46:29]

This is confusing. What's the cert we get from the identity? Obviously not the
|dtlscert|.

[hbos, 2015/08/14 14:09:39]

Yeah, two things called certificate is confusing... Not sure what the best way
is around it though. Perhaps there is a better name than DtlsCertificate or
perhaps certificate() could be called sslcertificate() but I would like to
minimize name changes in this already enormous CL. Hmmm...

SSLIdentity::certificate() gets an SSLCertificate which is a lower level concept
of a certificate (an abstract interface for "wrapping the SSL library's notion
of a certificate", it has various implementations just like there are various
SSLIdentity implementations). The specific implementations of SSLIdentity and
SSLCertificate interact with specific crypto libraries.
This goes to crypto stuff I don't understand.

The DtlsCertificate is a higher level concept of a certificate that just points
to the lower level stuff and is reference counted, not concerned about how the
crypto stuff works. It should be analogous to the RTCCertificate that the
specifications talk about. Something that can be passed around and which
specifies which underlying crypto magic to use.

[Henrik Grunell WebRTC, 2015/08/18 14:25:11]

OK. If this is clear in the DtlsCertificate class description (in its header), I
think it's fine.

       if (r)
         local_cert_report_id = r->id();
     }