-- v2: winex11: Get rid of X11DRV_XDND_HasHDROP helper. winex11: Use a custom IEnumFORMATETC interface implementation. winex11: Clear the XDND data object on drop event. winex11: Get rid of X11DRV_XDND_SendDropFiles helper. winex11: Assume that PostMessageW WM_DROPFILES succeeds. winex11: Only enter the CS to get a reference on the data object.