org-list: ignore lines with org-example property when creating structure

* lisp/org-list.el (org-list-struct): when a line has org-example
  property, skip the entire block. This is needed during export, for
  example when src blocks in org markup contain lists, and are
  returned verbatim because org isn't in the list of interpreted
  languages.

lisp/org-list.el

@@ -621,8 +621,8 @@ Assume point is at an item."
 	   (text-min-ind 10000)
 	   (item-re (org-item-re))
 	   (drawers-re (concat "^[ \t]*:\\("
-				     (mapconcat 'regexp-quote org-drawers "\\|")
-				     "\\):[ \t]*$"))
+			       (mapconcat 'regexp-quote org-drawers "\\|")
+			       "\\):[ \t]*$"))
 	   (inlinetask-re (and (featurep 'org-inlinetask)
 			       (org-inlinetask-outline-regexp)))
 	   (beg-cell (cons (point) (org-get-indentation)))
@@ -661,14 +661,22 @@ Assume point is at an item."
 		;; Jump to part 2.
 		(throw 'exit
 		       (setq itm-lst
-			     (if (not (looking-at item-re))
+			     (if (or (not (looking-at item-re))
+				     (get-text-property (point) 'org-example))
 				 (memq (assq (car beg-cell) itm-lst) itm-lst)
 			       (setq beg-cell (cons (point) ind))
 			       (cons (funcall assoc-at-point ind) itm-lst)))))
+	       ;; At a verbatim block, go before its beginning. Move
+	       ;; from eol to ensure `previous-single-property-change'
+	       ;; will return a value.
+	       ((get-text-property (point) 'org-example)
+		(goto-char (previous-single-property-change
+			    (point-at-eol) 'org-example nil lim-up))
+		(forward-line -1))
+	       ;; Looking at a list ending regexp. Dismiss useless
+	       ;; data recorded above BEG-CELL. Jump to part 2.
 	       ((and (not (eq org-list-ending-method 'indent))
 		     (looking-at org-list-end-re))
-		;; Looking at a list ending regexp. Dismiss useless
-		;; data recorded above BEG-CELL. Jump to part 2.
 		(throw 'exit
 		       (setq itm-lst
 			     (memq (assq (car beg-cell) itm-lst) itm-lst))))
@@ -732,10 +740,16 @@ Assume point is at an item."
 	      ;; part 3.
       	      (throw 'exit
 		     (push (cons 0 (funcall end-before-blank)) end-lst-2)))
+	     ;; At a verbatim block, move to its end. Point is at bol
+	     ;; and 'org-example property is set by whole lines:
+	     ;; `next-single-property-change' always return a value.
+	     ((get-text-property (point) 'org-example)
+	      (goto-char
+	       (next-single-property-change (point) 'org-example nil lim-down)))
+	     ;; Looking at a list ending regexp. Save point as an
+	     ;; ending position and jump to part 3.
 	     ((and (not (eq org-list-ending-method 'indent))
 		   (looking-at org-list-end-re))
-	      ;; Looking at a list ending regexp. Save point as an
-	      ;; ending position and jump to part 3.
 	      (throw 'exit (push (cons 0 (point-at-bol)) end-lst-2)))
 	     ;; Skip blocks, drawers, inline tasks and blank lines
 	     ;; along the way
@@ -765,14 +779,14 @@ Assume point is at an item."
 	      ;;
 	      ;; - ind is lesser or equal than previous item's. This
 	      ;;    is an ending position. Store it and proceed.
-	       (cond
-		((eq org-list-ending-method 'regexp))
-		((<= ind (cdr beg-cell))
-		 (push (cons ind (funcall end-before-blank)) end-lst-2)
-		 (throw 'exit nil))
-		((<= ind (nth 1 (car itm-lst-2)))
-		 (push (cons ind (point-at-bol)) end-lst-2)))
-	       (forward-line 1))))))
+	      (cond
+	       ((eq org-list-ending-method 'regexp))
+	       ((<= ind (cdr beg-cell))
+		(push (cons ind (funcall end-before-blank)) end-lst-2)
+		(throw 'exit nil))
+	       ((<= ind (nth 1 (car itm-lst-2)))
+		(push (cons ind (point-at-bol)) end-lst-2)))
+	      (forward-line 1))))))
       (setq struct (append itm-lst (cdr (nreverse itm-lst-2))))
       (setq end-lst (append end-lst (cdr (nreverse end-lst-2))))
       ;; 3. Correct ill-formed lists by making sure top item has the