Refile: Fix horrible bug

This bug would make refiling complain about the tree not being a tree
unless the *previous* content of the tree was a tree.  Pretty bad....

lisp/ChangeLog

@@ -1,3 +1,8 @@
+2009-08-05  Carsten Dominik  <carsten.dominik@gmail.com>
+
+	* org.el (org-paste-subtree): Test the kill ring entry if it is
+	going to be used.
+
 2009-08-04  Carsten Dominik  <carsten.dominik@gmail.com>
 
 	* org.el (org-table-map-tables): Make sure cursor is back at table

lisp/org.el

@@ -6184,12 +6184,13 @@ When FOR-YANK is set, this is called by `org-yank'.  In this case, do not
 move back over whitespace before inserting, and move point to the end of
 the inserted text when done."
   (interactive "P")
+  (setq tree (or tree (and kill-ring (current-kill 0))))
   (unless (org-kill-is-subtree-p tree)
     (error "%s"
      (substitute-command-keys
       "The kill is not a (set of) tree(s) - please use \\[yank] to yank anyway")))
   (let* ((visp (not (org-invisible-p)))
-	 (txt (or tree (and kill-ring (current-kill 0))))
+	 (txt tree)
 	 (^re (concat "^\\(" outline-regexp "\\)"))
 	 (re  (concat "\\(" outline-regexp "\\)"))
 	 (^re_ (concat "\\(\\*+\\)[  \t]*"))