Get selection start in content editable div

Question

READ BEFORE MARKING DUPLICATE:

1. The contenteditable div will not have child elements
2. I do not want a cross-browser solution, only Chrome support required
3. Only vanilla JS, no libraries.

I have looked up almost all the posts on Stackoverflow (would be quite surprising for me if this post turns out to be a duplicate), and found this fiddle: http://jsfiddle.net/cpatik/3QAeC/

Its getSelectionBegin code was:

function getSelectionBegin(element) {
    var caretOffset = 0;
    if (w3) {
    }
    else if (ie) {
        var textRange = document.selection.createRange();
        var preCaretTextRange = document.body.createTextRange();
        preCaretTextRange.moveToElementText(element);
        preCaretTextRange.setEndPoint("EndToStart", textRange);
        caretOffset = preCaretTextRange.text.length;
    }
    return caretOffset;
}

Notice the w3 part (which I require) is blank. Seemed to me like there's no method for getting selectionStart, but I assume someone might have developed a hack to get round this.

So the question:

How do I get the selection start in a content editable div ?

UPDATE:

As it turns out, there was a solution, but apparently missed by me due to the bug I had before