Bind a socket to a network if the network handle is set.

webrtc/base/macasyncsocket.h

Index: webrtc/base/macasyncsocket.h
diff --git a/webrtc/base/macasyncsocket.h b/webrtc/base/macasyncsocket.h
index 5861ee3276a7990b4552aceafe8c3c8b7d4a8031..5ab279a9782eee26c94adddaee27f6951045c841 100644
--- a/webrtc/base/macasyncsocket.h
+++ b/webrtc/base/macasyncsocket.h
@@ -52,6 +52,7 @@ class MacAsyncSocket : public AsyncSocket, public sigslot::has_slots<> {
   int EstimateMTU(uint16_t* mtu) override;
   int GetOption(Option opt, int* value) override;
   int SetOption(Option opt, int value) override;
+  int BindToNetwork(NetworkHandle handle) override;
 
   // For the MacBaseSocketServer to disable callbacks when process_io is false.
   void EnableCallbacks();