[PATCH 5/7] win32u: Update children with a surface when the parent window moves.

[Rémi Bernon]

From: Rémi Bernon

Since changes in a parent window state may affect the children state
in the driver, ensure the driver gets a chance to update its internal
state.
---
 dlls/win32u/window.c | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)

diff --git a/dlls/win32u/window.c b/dlls/win32u/window.c
index 10ecf4b8c60..ee532cb8459 100644
--- a/dlls/win32u/window.c
+++ b/dlls/win32u/window.c
@@ -1974,6 +1974,22 @@ static struct window_surface *get_window_surface( HWND hwnd, UINT swp_flags, BOO
     return new_surface;
 }

+static void update_children_window_state( HWND hwnd )
+{
+    HWND *children;
+    int i;
+
+    if (!(children = list_window_children( 0, hwnd, NULL, 0 ))) return;
+
+    for (i = 0; children[i]; i++)
+    {
+        if (!window_has_pixel_format( children[i] )) continue;
+        update_window_state( children[i] );
+    }
+
+    free( children );
+}
+
 /***********************************************************************
  *           apply_window_pos
  *
@@ -2117,6 +2133,7 @@ static BOOL apply_window_pos( HWND hwnd, HWND insert_after, UINT swp_flags, stru
         }

user_driver->pWindowPosChanged( hwnd, insert_after, swp_flags, &monitor_rects, get_driver_window_surface( new_surface, monitor_dpi ) );
+        update_children_window_state( hwnd );
     }

return ret;