[Ohrrpgce] SVN: teeemcee/8034 mac: Implement os_get_screen_size, so that window size changing works

[subversion at HamsterRepublic.com]

teeemcee
2016-06-05 05:28:19 -0700 (Sun, 05 Jun 2016)
140
mac: Implement os_get_screen_size, so that window size changing works

(gfx_sdl's reporting of desktop resolution didn't seem to be working)
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U   wip/os_unix_wm.c
U   wip/whatsnew.txt