Win32: the Property Browser remains visible when going full screen (C…

…TRL-F11)

On Windows when going full screen by pressing CTRL-F11 the Property Browser
window remained hidden behind the main window until one ALT-Tab-ed to it or
to another application and back.

This commit fixes it.

The fix is not mine. It comes from this Chinese fork:
https://gitee.com/zhongzhiSys/SolveSpace
where they mostly took 2.3 and started selectively merging fixes from 3.x
with their own commit messages. There are however original fixes like this
one interspersed with the merges. I have not finished going through
everything.

The original commit hash: de8e59bbcc25156f83bda45eedf775aa6d3d65d2
And message: "修正全屏后无法显示属性窗口的问题"

src/platform/guiwin.cpp

@@ -1146,7 +1146,7 @@ class WindowImplWin32 final : public Window {
             sscheck(GetMonitorInfo(MonitorFromWindow(hWindow, MONITOR_DEFAULTTONEAREST), &mi));
 
             sscheck(SetWindowLong(hWindow, GWL_STYLE, style & ~WS_OVERLAPPEDWINDOW));
-            sscheck(SetWindowPos(hWindow, HWND_TOP,
+            sscheck(SetWindowPos(hWindow, HWND_NOTOPMOST,
                                  mi.rcMonitor.left, mi.rcMonitor.top,
                                  mi.rcMonitor.right - mi.rcMonitor.left,
                                  mi.rcMonitor.bottom - mi.rcMonitor.top,