Refresh focus on FocusIn events

Refresh focus on FocusIn events

To avoid some oddities, awesome sets the input focus lazily. Instead of
immediately sending everything to the X11 server, awesome just sets a flag "have
to update the focus later".

However, this can cause problems. As Stefan noticed, awesome can forget about
focus changes on FocusIn events when such an event comes in while we still have
a pending focus change.

The fix here is to send out the pending focus change before we record the fact
that another client now acquired the input focus.

Reported-By: Stefan Haller <haliner@googlemail.com>
Signed-off-by: Uli Schlachter <psychon@znc.in>