key_mobile_sites_smooth: Reload pages before scrolling for LinkedIn and Wowwiki

tools/perf/page_sets/key_mobile_sites_smooth.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.page import page as page_module
 from telemetry.page import page_set as page_set_module
 
 from page_sets import key_mobile_sites_pages
 
 
 def _IssueMarkerAndScroll(action_runner):
@@ skipping 119 matching lines @@
       key_mobile_sites_pages.FacebookPage,
       key_mobile_sites_pages.YoutubeMobilePage,
       key_mobile_sites_pages.LinkedInPage,
       key_mobile_sites_pages.YahooAnswersPage,
       key_mobile_sites_pages.GoogleNewsMobilePage,
     ]
     for page_class in predefined_page_classes:
       self.AddUserStory(
         _CreatePageClassWithSmoothInteractions(page_class)(self))
 
+    # Rerun the LinkedIn page to take the benefit of shader disk cache for
+    # gpu rasterization. Make sure the rerun is after the original page.
+    self.AddUserStory(
+      _CreatePageClassWithSmoothInteractions(
+        key_mobile_sites_pages.LinkedInPage)(self, name='LinkedIn - rerun'))
+
     # Add pages with custom page interaction logic.
 
     # Page behaves non-deterministically, replaced with test version for now.
     # self.AddUserStory(GroupClonedSmoothPage(self))
     # mean_input_event_latency cannot be tracked correctly for
     # GroupClonedListImagesPage.
     # See crbug.com/409086.
     # self.AddUserStory(GroupClonedListImagesSmoothPage(self))
     self.AddUserStory(GoogleNewsMobile2SmoothPage(self))
     self.AddUserStory(AmazonNicolasCageSmoothPage(self))
@@ skipping 96 matching lines @@
       # Why: #1 Alexa sports
       'http://sports.yahoo.com/',
       # Why: Top tech blog
       'http://techcrunch.com',
       # Why: #6 Alexa sports
       'http://mlb.com/',
       # Why: #14 Alexa California
       'http://www.sfgate.com/',
       # Why: Non-latin character set
       'http://worldjournal.com/',
-      # Why: Mobile wiki
-      'http://www.wowwiki.com/World_of_Warcraft:_Mists_of_Pandaria',
       # Why: #15 Alexa news
       'http://online.wsj.com/home-page',
       # Why: Image-heavy mobile site
       'http://www.deviantart.com/',
       # Why: Top search engine
       ('http://www.baidu.com/s?wd=barack+obama&rsv_bp=0&rsv_spt=3&rsv_sug3=9&'
        'rsv_sug=0&rsv_sug4=3824&rsv_sug1=3&inputT=4920'),
       # Why: Top search engine
       'http://www.bing.com/search?q=sloths',
       # Why: Good example of poor initial scrolling
       'http://ftw.usatoday.com/2014/05/spelling-bee-rules-shenanigans'
     ]
 
     for url in urls_list:
       self.AddUserStory(KeyMobileSitesSmoothPage(url, self))
+
+    # Why: Mobile wiki
+    wow_url = 'http://www.wowwiki.com/World_of_Warcraft:_Mists_of_Pandaria'
+    self.AddUserStory(KeyMobileSitesSmoothPage(url=wow_url, page_set=self))
+    # Rerun the wowwiki page to take the benefit of shader disk cache for
+    # gpu rasterization. Make sure the rerun is after the original page.
+    self.AddUserStory(KeyMobileSitesSmoothPage(

[jdduke (slow), 2015/02/26 22:05:04]

Are we guaranteed that the same page will run on the same device? 

Would it make sense to have it done atomically, e.g., have a page that loads,
scrolls, then reloads and scrolls, and we only capture the second sequence?
Calling that the rerun?

[Yufeng Shen (Slow to review), 2015/02/26 22:15:04]

I think one benchmark always runs on the same devices. And different benchmarks
can run on different devices.
 
I was thinking of avoiding bias toward first run or second run. So I decide to
capture both.

+      url=wow_url, page_set=self, name=wow_url + ' - rerun'))