CalcChildScroll

[Bill Medland]

Does anyone have a problem with the following fix to
windows/mdi.c/CalcChildScroll?  It fixes a problem for one product but I am
not in a position to test it thoroughly.

When measuring the union of the children rectangles only the visible
children should be included:

..
          }
          else if( pWnd->dwStyle & WS_VISIBLE)
              UnionRect( &childRect, &pWnd->rectWindow, &childRect );

This stops scrollbars appearing and disappearing while resizing apparently
empty mdi clients etc.

Bill Medland