[Bug 55066] user32:msg - test_button_messages() sometimes gets WM_SIZE instead of WM_SETFOCUS in Wine

[WineHQ Bugzilla]

https://bugs.winehq.org/show_bug.cgi?id=55066

--- Comment #5 from Esme Povirk  ---
I tried running this in a loop until a button test failed, but I ended up
getting a different failure: BM_SETSTYLE on a button got an unexpected
WM_MOUSEACTIVATE which was the result of the WM focusing our window when it was
initially shown.

This sort of makes sense, I suppose. That message takes time to get to us, so
perhaps the test completes before the WM can do that in most cases.