Update perf page_set to use story_set

tools/perf/page_sets/tough_pinch_zoom_cases.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 ToughPinchZoomCasesPage(page_module.Page):
 
   def __init__(self, url, page_set, name=''):
     super(ToughPinchZoomCasesPage, self).__init__(
         url=url, page_set=page_set, name=name,
         shared_page_state_class=shared_page_state.SharedDesktopPageState,
         credentials_path = 'data/credentials.json')
     self.archive_data_file = 'data/tough_pinch_zoom_cases.json'
@@ skipping 210 matching lines @@
   def __init__(self, page_set):
     super(YahooAnswersPage, self).__init__(
       url='http://answers.yahoo.com',
       page_set=page_set)
 
   def RunPageInteractions(self, action_runner):
     with action_runner.CreateGestureInteraction('PinchAction'):
       action_runner.PinchElement(selector='#ya-content-apps')
 
 
-class ToughPinchZoomCasesPageSet(page_set_module.PageSet):
+class ToughPinchZoomCasesPageSet(story.StorySet):
 
   """ Set of pages that are tricky to pinch-zoom """
 
   def __init__(self):
     super(ToughPinchZoomCasesPageSet, self).__init__(
       archive_data_file='data/tough_pinch_zoom_cases.json',
-      bucket=page_set_module.PARTNER_BUCKET)
+      cloud_storage_bucket=story.PARTNER_BUCKET)
 
     self.AddUserStory(GoogleSearchPage(self))
     self.AddUserStory(GmailPage(self))
     self.AddUserStory(GoogleCalendarPage(self))
     self.AddUserStory(GoogleImageSearchPage(self))
     self.AddUserStory(GooglePlusPage(self))
     self.AddUserStory(YoutubePage(self))
     self.AddUserStory(BlogSpotPage(self))
     self.AddUserStory(FacebookPage(self))
     self.AddUserStory(LinkedinPage(self))
@@ skipping 18 matching lines @@
 
     self.AddUserStory(YahooGamePage(self))
 
     # Why: #1 Alexa recreation
     self.AddUserStory(ToughPinchZoomCasesPage('http://booking.com', self))
 
     self.AddUserStory(YahooAnswersPage(self))
 
     # Why: #1 Alexa sports
     self.AddUserStory(ToughPinchZoomCasesPage('http://sports.yahoo.com/', self))