Bug 1621036 - Enable DTLS 1.3 supported_versions workaround for interop between pre/post-Fx75 WebRTC. r=mt

Enable the NSS workaround introduced in bug 1619102, for DTLS 1.3 WebRTC clients.

Differential Revision: https://phabricator.services.mozilla.com/D66094

--HG--
extra : moz-landing-system : lando

media/mtransport/transportlayerdtls.cpp

@@ -501,6 +501,15 @@ bool TransportLayerDtls::Setup() {
       MOZ_MTLOG(ML_ERROR, "Couldn't set identity");
       return false;
     }
+
+    if (maxVersion_ >= Version::DTLS_1_3) {
+      MOZ_MTLOG(ML_INFO, "Setting DTLS1.3 supported_versions workaround");
+      rv = SSL_SetDtls13VersionWorkaround(ssl_fd.get(), PR_TRUE);
+      if (rv != SECSuccess) {
+        MOZ_MTLOG(ML_ERROR, "Couldn't set DTLS1.3 workaround");
+        return false;
+      }
+    }
   } else {
     MOZ_MTLOG(ML_INFO, "Setting up DTLS as server");
     // Server side