How to check all the GRANTED Permission of all the installed apps whose sdk version is less than 23 like viber

Question

Here is my code please check

List<String> getGrantedPermissions(final String appPackage) {
List<String> granted = new ArrayList<String>();
try {
    PackageInfo pi = getPackageManager().getPackageInfo(appPackage, PackageManager.GET_PERMISSIONS);
    for (int i = 0; i < pi.requestedPermissions.length; i++) {
        if ((pi.requestedPermissionsFlags[i] & PackageInfo.REQUESTED_PERMISSION_GRANTED) != 0) {
            granted.add(pi.requestedPermissions[i]);
        }
    }
} catch (Exception e) {
}
return granted;

}

It works with the installed apps who has used sdk version greater then 23 but apllication like for eg viber is showing true even if we disable the apps permission

is there any solution for this please help me out here