prevent crash

app/src/main/java/eu/faircode/email/ConnectionHelper.java

@@ -442,7 +442,8 @@ public class ConnectionHelper {
     }
 
     static Boolean isPrivateDnsActive(Context context) {
-        if (Build.VERSION.SDK_INT < Build.VERSION_CODES.M)
+        try {
+            if (Build.VERSION.SDK_INT < Build.VERSION_CODES.P)
                 return null;
             ConnectivityManager cm = Helper.getSystemService(context, ConnectivityManager.class);
             if (cm == null)
@@ -454,10 +455,15 @@ public class ConnectionHelper {
             if (props == null)
                 return null;
             return props.isPrivateDnsActive();
+        } catch (Throwable ex) {
+            Log.e(ex);
+            return null;
+        }
     }
 
     static String getPrivateDnsServerName(Context context) {
-        if (Build.VERSION.SDK_INT < Build.VERSION_CODES.M)
+        try {
+            if (Build.VERSION.SDK_INT < Build.VERSION_CODES.P)
                 return null;
             ConnectivityManager cm = Helper.getSystemService(context, ConnectivityManager.class);
             if (cm == null)
@@ -469,6 +475,10 @@ public class ConnectionHelper {
             if (props == null)
                 return null;
             return props.getPrivateDnsServerName();
+        } catch (Throwable ex) {
+            Log.e(ex);
+            return null;
+        }
     }
 
     static boolean isIoError(Throwable ex) {