[Bug 11424] Canon Digital Photo Professional (DPP) pane refresh

http://bugs.winehq.org/show_bug.cgi?id=11424

--- Comment #23 from Nikolay Sivov   2009-10-17 09:08:55 ---
Created an attachment (id=24198)
 --> (http://bugs.winehq.org/attachment.cgi?id=24198)
treeview background fill fix

Here is an updated version of the same patch.

Problem description:

For subclassed controls (like in this application) it's ok not to forward
WM_ERASEBKGND to original window procedure, instead only WM_PAINT is forwarded
with NULL wParam which leads to BeginPaint/EndPaint sequence. After that
returned PAINTSTRUCT contains not zero fErase field - it means we need to fill
background before making main WM_PAINT painting.

This fact currently is completely ignored for Wine common controls.