[Bug 38275] DeferWindowPos accept NULL HWND and fail at EndDeferWindowPos( )

https://bugs.winehq.org/show_bug.cgi?id=38275

--- Comment #4 from Ivan_83  ---
I think wine should return hdwp on fail and on success.

https://msdn.microsoft.com/en-us/library/windows/desktop/ms632681(v=vs.85).a...
===============================================================================
Return value

Type:

Type: HDWP

The return value identifies the updated multiple-window – position structure.
The handle returned by this function may differ from the handle passed to the
function. The new handle that this function returns should be passed during the
next call to the DeferWindowPos or EndDeferWindowPos function.

If insufficient system resources are available for the function to succeed, the
return value is NULL. To get extended error information, call GetLastError.
===============================================================================

so NULL returned only on mallocal/realloc hdwp fail.