user32: Add a test for reparenting a WS_POPUP window to a WS_CHILD parent. Take 2.

[Dmitry Timoshkov]

Marvin <testbot at testbot.winehq.org> wrote:

> === W7PROX64 (64 bit win) ===
> win.c:3480: Test failed: SetForegroundWindow() failed

That's pretty strange, a standalone test I sent to testbot passed
without any failures.

-- 
Dmitry.