For VPN network, use the underlying network type as its type.

webrtc/api/android/java/src/org/webrtc/NetworkMonitorAutoDetect.java

Index: webrtc/api/android/java/src/org/webrtc/NetworkMonitorAutoDetect.java
diff --git a/webrtc/api/android/java/src/org/webrtc/NetworkMonitorAutoDetect.java b/webrtc/api/android/java/src/org/webrtc/NetworkMonitorAutoDetect.java
index 270fca0b31d2abba4d506d1a89bcfc3d23760105..3046ab20c550f17829e679d595754ea06860a73f 100644
--- a/webrtc/api/android/java/src/org/webrtc/NetworkMonitorAutoDetect.java
+++ b/webrtc/api/android/java/src/org/webrtc/NetworkMonitorAutoDetect.java
@@ -288,6 +288,12 @@ public class NetworkMonitorAutoDetect extends BroadcastReceiver {
       }
 
       NetworkState networkState = getNetworkState(network);
+      if (networkState.connected && networkState.getNetworkType() == ConnectivityManager.TYPE_VPN) {
+        // If a VPN network is in place, we can find the underlying network type via querying the
+        // active network info thanks to
+        // https://android.googlesource.com/platform/frameworks/base/+/d6a7980d
+        networkState = getNetworkState();
+      }
       ConnectionType connectionType = getConnectionType(networkState);
       if (connectionType == ConnectionType.CONNECTION_NONE) {
         // This may not be an error. The OS may signal a network event with connection type