(window-iso-combination-p, window-iso-combinations):

(window-iso-combination-p, window-iso-combinations):
New functions.
(walk-windows, get-window-with-predicate)
(get-buffer-window-list, one-window-p): Fix doc-string.
(window-in-direction): The column / row value of `posn-at-point'
can be nil for the mini-window, guard against that.
(resize-mini-window): Make this usable.  It's needed, for
example, by ispell.el.
(resize-window): Handle case where window argument denotes a
minibuffer window.
(window-children-count): Remove.
(split-window): Fix some broken size calculations.
Fixes to window.el accumluated over the past months.

* window.el (window-iso-combination-p, window-iso-combinations):
New functions.
(walk-windows, get-window-with-predicate)
(get-buffer-window-list, one-window-p): Fix doc-string.
(window-in-direction): The column / row value of `posn-at-point'
can be nil for the mini-window, guard against that.
(resize-mini-window): Make this usable.  It's needed, for
example, by ispell.el.
(resize-window): Handle case where window argument denotes a
minibuffer window.
(window-children-count): Remove.
(split-window): Fix some broken size calculations.