Delete left-over method SocketFactory::CreateAsyncSocket

Bug: webrtc:13065
Change-Id: I604fc8c37bfde762a992adfe82f187bc3dd1800d
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/231231
Reviewed-by: Mirko Bonadei <mbonadei@webrtc.org>
Commit-Queue: Niels Moller <nisse@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#34936}
diff --git a/rtc_base/socket_factory.h b/rtc_base/socket_factory.h
index b43bd1b..882b44f 100644
--- a/rtc_base/socket_factory.h
+++ b/rtc_base/socket_factory.h
@@ -21,10 +21,6 @@
 
   // Returns a new socket.  The type can be SOCK_DGRAM and SOCK_STREAM.
   virtual Socket* CreateSocket(int family, int type) = 0;
-  // TODO(nisse): Delete old alias, ASAP when downstream code is updated.
-  virtual Socket* CreateAsyncSocket(int family, int type) {
-    return CreateSocket(family, type);
-  }
 };
 
 }  // namespace rtc