bug#18528: 24.3.93; Crash during restoration of frameset from desktop

[martin rudalics]

> So now I don't understand why you asked about rounding up, since we
> evidently already do.

Not everywhere.  For example, we don't in FRAME_MESSAGE_BUF_SIZE and
FRAME_CURSOR_X_LIMIT.  And the following check in compute_motion of
indent.c seems dubious as well.

          if (!NILP (Vtruncate_partial_width_windows)
              && (total_width < FRAME_COLS (XFRAME (WINDOW_FRAME (win)))))

martin