Make sure that returned window belongs to correct thread when checking

windows/win.c

@@ -361,41 +361,39 @@ HWND WIN_FindWinToRepaint( HWND hwnd )
 
     for ( ; pWnd ; WIN_UpdateWndPtr(&pWnd,pWnd->next))
     {
-        if (!(pWnd->dwStyle & WS_VISIBLE))
-        {
-            TRACE("skipping window %04x\n",
-                         pWnd->hwndSelf );
-        }
-        else if ((pWnd->hrgnUpdate || (pWnd->flags & WIN_INTERNAL_PAINT)) &&
+        if (!(pWnd->dwStyle & WS_VISIBLE)) continue;
+        if ((pWnd->hrgnUpdate || (pWnd->flags & WIN_INTERNAL_PAINT)) &&
             GetWindowThreadProcessId( pWnd->hwndSelf, NULL ) == GetCurrentThreadId())
             break;
-        
-        else if (pWnd->child )
+        if (pWnd->child )
+        {
             if ((hwndRet = WIN_FindWinToRepaint( pWnd->child->hwndSelf )) )
             {
                 WIN_ReleaseWndPtr(pWnd);
                 return hwndRet;
             }
-    
+        }
     }
 
     if(!pWnd)
     {
+        TRACE("nothing found\n");
         return 0;
     }
-    
     hwndRet = pWnd->hwndSelf;
 
     /* look among siblings if we got a transparent window */
-    while (pWnd && ((pWnd->dwExStyle & WS_EX_TRANSPARENT) ||
-                    !(pWnd->hrgnUpdate || (pWnd->flags & WIN_INTERNAL_PAINT))))
+    while (pWnd)
     {
-        WIN_UpdateWndPtr(&pWnd,pWnd->next);
-    }
-    if (pWnd)
+        if (!(pWnd->dwExStyle & WS_EX_TRANSPARENT) &&
+            (pWnd->hrgnUpdate || (pWnd->flags & WIN_INTERNAL_PAINT)) &&
+            GetWindowThreadProcessId( pWnd->hwndSelf, NULL ) == GetCurrentThreadId())
         {
             hwndRet = pWnd->hwndSelf;
             WIN_ReleaseWndPtr(pWnd);
+            break;
+        }
+        WIN_UpdateWndPtr(&pWnd,pWnd->next);
     }
     TRACE("found %04x\n",hwndRet);
     return hwndRet;