Close webrtc socket before closing the PeerConnection.

PiperOrigin-RevId: 522140908

connections/implementation/mediums/webrtc/connection_flow.cc

@@ -495,12 +495,17 @@ bool ConnectionFlow::CloseOnSignalingThread() {
     return false;
   }
   state_ = State::kEnded;
+  // Close the socket wrapper before terminating the PeerConnection
+  // since the teardown process of the PC may close threads that are
+  // otherwise depended upon by objects kept alive by the socket_wrapper.
+  if (socket_wrapper_.IsValid()) socket_wrapper_.Close();
+
   // This prevents other tasks from queuing on the signaling thread for this
   // object.
   auto pc = GetAndResetPeerConnection();
 
   NEARBY_LOG(INFO, "Closing WebRTC peer connection.");
-  // NOTE: Closing the peer conection will close the data channel and thus the
+  // NOTE: Closing the peer connection will close the data channel and thus the
   // socket implicitly.
   if (pc) pc->Close();
   NEARBY_LOG(INFO, "Closed WebRTC peer connection.");

connections/implementation/mediums/webrtc/webrtc_socket_impl.cc

@@ -67,8 +67,12 @@ WebRtcSocket::WebRtcSocket(
 WebRtcSocket::~WebRtcSocket() {
   NEARBY_LOGS(INFO) << "WebRtcSocket::~WebRtcSocket(" << name_
                     << ") this: " << this;
-  data_channel_->UnregisterObserver();
-  Close();
+
+  if (!IsClosed()) {
+    data_channel_->UnregisterObserver();
+    Close();
+  }
+
   NEARBY_LOGS(INFO) << "WebRtcSocket::~WebRtcSocket(" << name_
                     << ") this: " << this << " done";
 }