Method getRootDomain

app/src/main/java/eu/faircode/email/UriHelper.java:123–140

(Context context, String host)

    }

    static String getRootDomain(Context context, String host) {
        if (host == null)
            return null;
        String tld = getTld(context, host);
        if (tld == null)
            return null;
        if (tld.equalsIgnoreCase(host))
            return null;
        int len = host.length() - tld.length() - 1;
        if (len < 0) {
            Log.e("getRootDomain host=" + host + " tld=" + tld);
            return null;
        }
        int dot = host.substring(0, len).lastIndexOf('.');
        if (dot < 0)
            return host;
        return host.substring(dot + 1);
    }

    static boolean isTld(Context context, String host) {
        if (host == null)