disable chrome extension's badge

Question

I am developing a chrome extension that shows notifications.
I am showing the notifications using these functions chrome.browserAction.setBadgeBackgroundColor and chrome.browserAction.setBadgeText.
This is what it looks like:

After the user have seen the notifications I want to remove this badge.

I have tried to make it transparent but this was the result:

Can anyone help me how to remove the badge, or if there is another way that makes what I want?

Solution
When writing an empty text, the badge goes away.

Answer 1

To remove the badge count, simply set the text as an empty string:

chrome.browserAction.setBadgeText({
    'text': '' //an empty string displays nothing!
});

Answer 2

Be aware if you set badge for especially tab to unset the text for this one:

chrome.tab.query({currentWindow: true, active: true}, function(tabs) {
    var tab = tabs[0];
    chrome.browserAction.setBadgeText({
        text: ''
        tabId: theTabId
    });
});