In the current Suite source, your TODO comment and the following two lines of codes are as follows:
<pre>
888             // Strip out any null bytes in the content title, since the
889             // underlying widget implementations of nsWindow::SetTitle pass
890             // null-terminated strings to system APIs.
891             if (this.docShell.contentViewer)
892               docTitle = this.contentTitle.replace(/\0+/g, "");
</pre>