help-with-tutorial buffer-read-only fix

* lisp/tutorial.el (help-with-tutorial):
Ensure local variables don't happen to make the buffer read-only.

Fixes: debbugs:11127

lisp/ChangeLog

+2012-03-30  Glenn Morris  <rgm@gnu.org>
+
+	* tutorial.el (help-with-tutorial): Ensure local variables don't
+	happen to make the buffer read-only.  (Bug#11127)
+
 2012-03-30  Stefan Monnier  <monnier@iro.umontreal.ca>
 
 	* progmodes/perl-mode.el (perl-indent-line): Use `noindent' in strings.

lisp/tutorial.el

@@ -832,6 +832,7 @@ Run the Viper tutorial? "))
               (insert-file-contents (tutorial--saved-file))
 	      (let ((enable-local-variables :safe))
 		(hack-local-variables))
+              (setq buffer-read-only nil) ; bug#11118
               (goto-char (point-min))
               (setq old-tut-point
                     (string-to-number
@@ -849,6 +850,7 @@ Run the Viper tutorial? "))
           (insert-file-contents (expand-file-name filename tutorial-directory))
 	  (let ((enable-local-variables :safe))
 	    (hack-local-variables))
+          (setq buffer-read-only nil) ; bug#11118
           (forward-line)
           (setq tutorial--point-before-chkeys (point-marker)))