My bad: The second line of the doc-string of `window-combination-limit'
is silly. Please revert this part of your patch and change the
doc-string in the Emacs-24.3 branch to:
DEFUN ("window-combination-limit", Fwindow_combination_limit,
Swindow_combination_limit, 1, 1, 0,
doc: /* Return combination limit of window WINDOW.
If the return value is nil, child windows of WINDOW can be recombined with
WINDOW's siblings. A return value of t means that child windows of
WINDOW are never \(re-)combined with WINDOW's siblings.
WINDOW must be a valid window. The return value is meaningful for
internal windows only. */)