fixed possible problem with cache.action

gluon/cache.py

@@ -606,8 +606,7 @@ class Cache(object):
             def wrapped_f():
                 if current.request.env.request_method != 'GET':
                     return func()
-                if time_expire:
+
-                    cache_control = 'max-age=%(time_expire)s, s-maxage=%(time_expire)s' % dict(time_expire=time_expire)
                 if quick:
                     session_ = True if 'S' in quick else False
                     vars_ = True if 'V' in quick else False
@@ -615,13 +614,18 @@ class Cache(object):
                     user_agent_ = True if 'U' in quick else False
                     public_ = True if 'P' in quick else False
                 else:
-                        session_, vars_, lang_, user_agent_, public_ = session, vars, lang, user_agent, public
+                    (session_, vars_, lang_, user_agent_, public_) = \
+                        (session, vars, lang, user_agent, public)
+
+                if time_expire:
+                    cache_control = 'max-age=%(time_expire)s, s-maxage=%(time_expire)s' % dict(time_expire=time_expire)
                     if not session_ and public_:
                         cache_control += ', public'
                         expires = (current.request.utcnow + datetime.timedelta(seconds=time_expire)).strftime('%a, %d %b %Y %H:%M:%S GMT')
                     else:
                         cache_control += ', private'
                         expires = 'Fri, 01 Jan 1990 00:00:00 GMT'
+
                 if cache_model:
                     #figure out the correct cache key
                     cache_key = [current.request.env.path_info, current.response.view]