Update perf page_set to use story_set

tools/perf/page_sets/typical_25.py

 # Copyright 2014 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
+from telemetry import story
+from telemetry.page import page as page_module
 from telemetry.page import shared_page_state
-from telemetry.page import page as page_module
-from telemetry.page import page_set as page_set_module
 
 
 class Typical25Page(page_module.Page):
 
   def __init__(self, url, page_set, run_no_page_interactions):
     super(Typical25Page, self).__init__(
         url=url, page_set=page_set,
         shared_page_state_class=shared_page_state.SharedDesktopPageState)
     self.archive_data_file = 'data/typical_25.json'
     self._run_no_page_interactions = run_no_page_interactions
 
   def RunPageInteractions(self, action_runner):
     if self._run_no_page_interactions:
       return
     with action_runner.CreateGestureInteraction('ScrollAction'):
       action_runner.ScrollPage()
 
 
-class Typical25PageSet(page_set_module.PageSet):
+class Typical25PageSet(story.StorySet):
 
   """ Pages designed to represent the median, not highly optimized web """
 
   def __init__(self, run_no_page_interactions=False):
     super(Typical25PageSet, self).__init__(
       archive_data_file='data/typical_25.json',
-      bucket=page_set_module.PARTNER_BUCKET)
+      cloud_storage_bucket=story.PARTNER_BUCKET)
 
     urls_list = [
       # Why: Alexa games #48
       'http://www.nick.com/games',
       # Why: Alexa sports #45
       'http://www.rei.com/',
       # Why: Alexa sports #50
       'http://www.fifa.com/',
       # Why: Alexa shopping #41
       'http://www.gamestop.com/ps3',
@@ skipping 25 matching lines @@
       'http://www.theverge.com/2013/3/5/4061684/inside-ted-the-smartest-bubble-in-the-world',
       'http://www.airbnb.com/',
       'http://www.ign.com/',
       # Why: Alexa health #25
       'http://www.fda.gov',
     ]
 
     for url in urls_list:
       self.AddUserStory(
         Typical25Page(url, self, run_no_page_interactions))