NetworkRequestDialog: Exit the dialog on connect failure

Connection failure (similar to connection success) is the end of the
processng of a request. We should dismiss the dialog on connection
failure.

Bug: 158844146
Test: Manual tests - Simulate connection failure and ensure that the
dialog vanishes with a toast.

Change-Id: I625ca76298ed549dbed76d398aea0c957c9102fc

src/com/android/settings/wifi/NetworkRequestDialogBaseFragment.java

@@ -21,7 +21,6 @@ import android.content.Context;
 import android.content.DialogInterface;
 import android.content.Intent;
 import android.net.wifi.ScanResult;
-import android.net.wifi.WifiConfiguration;
 import android.net.wifi.WifiManager.NetworkRequestUserSelectionCallback;
 
 import androidx.annotation.NonNull;
@@ -91,7 +90,4 @@ abstract public class NetworkRequestDialogBaseFragment extends InstrumentedDialo
 
     protected void onMatch(List<ScanResult> scanResults) {
     }
-
-    protected void onUserSelectionConnectFailure(WifiConfiguration wificonfiguration) {
-    }
 }