Fix global dynamic variables in org-special-blocks.el.

Thanks to Martyn Jago for this patch.

lisp/org-special-blocks.el

@@ -79,17 +79,17 @@ seen.  This is run after a few special cases are taken care of."
 (add-hook 'org-export-latex-after-blockquotes-hook
 	  'org-special-blocks-convert-latex-special-cookies)
 
-(defvar line)
+(defvar org-special-blocks-line)
 (defun org-special-blocks-convert-html-special-cookies ()
   "Converts the special cookies into div blocks."
-  ;; Uses the dynamically-bound variable `line'.
-  (when (string-match "^ORG-\\(.*\\)-\\(START\\|END\\)$" line)
+  ;; Uses the dynamically-bound variable `org-special-blocks-line'.
+  (when (string-match "^ORG-\\(.*\\)-\\(START\\|END\\)$" org-special-blocks-line)
     (message "%s" (match-string 1))
-    (when (equal (match-string 2 line) "START")
+    (when (equal (match-string 2 org-special-blocks-line) "START")
       (org-close-par-maybe)
-      (insert "\n<div class=\"" (match-string 1 line) "\">")
+      (insert "\n<div class=\"" (match-string 1 org-special-blocks-line) "\">")
       (org-open-par))
-    (when (equal (match-string 2 line) "END")
+    (when (equal (match-string 2 org-special-blocks-line) "END")
       (org-close-par-maybe)
       (insert "\n</div>")
       (org-open-par))