How can i use safe-browsing application object to determine whether a url is reported as phishing site or malware site?

Question

Here is code snippet:

Components.classes['@mozilla.org/safebrowsing/application;1']
    .getService().wrappedJSObject.malwareWarden.listManager_
    .safeLookup(test_url, function(tableName){
        if (tableName == 'goog-phish-shavar' || tableNmae == 'goog-malware-shavar') {
            alert('This is reported by Google! ');
        };
});

It works fine, but I don't think it is the 'right' way...

What if user change the DataProvider?