Fix size calculation in window--max-delta-1.

* window.el (window--max-delta-1): Round down when calculating
how many lines/columns we can get from a window.

lisp/ChangeLog

+2014-03-01  Martin Rudalics  <rudalics@gmx.at>
+
+	* window.el (window--max-delta-1): Round down when calculating
+	how many lines/columns we can get from a window.
+
 2014-03-01  Glenn Morris  <rgm@gnu.org>
 
 	* isearch.el (search-invisible): Doc fix.

lisp/window.el

@@ -1470,7 +1470,7 @@ by which WINDOW can be shrunk."
 		  (setq delta
 			(+ delta
 			   (max
-			    (- (window-size sub horizontal pixelwise 'ceiling)
+			    (- (window-size sub horizontal pixelwise 'floor)
 			       (window-min-size
 				sub horizontal ignore pixelwise))
 			    0)))))