bug#53170: 29.0.50; Can't repetitively click next node button inside Info header line

[Juri Linkov]

>> >> But I don't know how important is the feature of selecting/dragging the 
>> >> header-line?
>> >
>> > I don't think I understand how 2 clicks one after another are taken as
>> > a drag-mouse event.  Can you tell why this happens?
>> 
>> Actually, its's mouse-select-window that steals the click.
>> There is no need to bind mouse-1 to mouse-select-window
>> because the window is selected anyway, so this patch fixes
>> the reported problem:
>
> Thanks, this LGTM.

So now pushed to master.