user32: Change SetFocus behavior on windows with parent and no WS_CHILD flag

[Marvin]

Hi,

While running your changed tests on Windows, I think I found new failures.
Being a bot and all I'm not very good at pattern recognition, so I might be
wrong, but could you please double-check?
Full results can be found at
https://testbot.winehq.org/JobDetails.pl?Key=6004

Your paranoid android.


=== w8 (32 bit win) ===
win.c:6205: Test failed: wrong error 31