Check for loaded pages in Chrome extensions
===

I have this piece of code in my background.js:

    chrome.tabs.onUpdated.addListener(function(tabId, changeInfo, tab) {
        if (changeInfo.status == 'complete') {
            chrome.tabs.executeScript(null, {code:"alert('Loaded');"});
        }
    });
This should give me an alert every time a page is loaded, but it doesn't..