org-src.el (org-edit-src-exit): Don't add indentation on empty lines

* org-src.el (org-edit-src-exit): Don't add indentation on
empty lines.

TINYCHANGE

lisp/org-src.el

@@ -737,8 +737,10 @@ with \",*\", \",#+\", \",,*\" and \",,#+\"."
       (unless (or single preserve-indentation (= total-nindent 0))
 	(setq indent (make-string total-nindent ?\ ))
 	(goto-char (point-min))
-	(while (re-search-forward "^" nil t)
-	  (replace-match indent)))
+        (while (re-search-forward "^" nil t)
+          (if (not (looking-at "$"))
+              (replace-match indent)
+	    (forward-char 1))))
       (if (org-bound-and-true-p org-edit-src-picture)
 	  (setq total-nindent (+ total-nindent 2)))
       (setq code (buffer-string))