Fixed popups getting blocked by modal windows.

Fixed popups getting blocked by modal windows.

In the case of a file dialog with a completer, the completion list view
is a popup that is not a transient child of the file dialog. Thus it
ends up getting its blockedByModal flag set due to the file dialog
window being a modal window.

To prevent this we make sure popups don't get blocked by modal windows,
as they were special cased and processed before modal windows in Qt 4.x.

Change-Id: Id5688cfb1534541cd1678b1e53d75e34a68f9b8e
Reviewed-by: Lars Knoll <lars.knoll@nokia.com>
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@nokia.com>