[wxMac] focus handling fix in 2.8 for 10.5 -please test

[Stefan Csomor]

Hi

there have been two reports of wrong behavior or even crashes when 
running the latest 2.8 releases under 10.5. The reason seems to be a 
change in the handling of keyboard focus:

https://sourceforge.net/tracker/?func=detail&atid=109863&aid=1834762&group_id=9863

http://thread.gmane.org/gmane.comp.lib.wxwidgets.devel/93681

After many hourse of trials, I think I've found a solution that doesn't 
involve too many changes, I've committed a fix to 
src/mac/carbon/window.cpp in WX_2_8_BRANCH, svn rev 50127, I'd be glad 
if you could test this change both under 10.5 if possible, as well as 
under 10.4. or 10.3 and report any issues you might have with that change

Thanks,

Stefan