[system health] Add flipboard to system health stories.

tools/perf/page_sets/system_health/browsing_stories.py

 # Copyright 2016 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 page_sets.system_health import platforms
 from page_sets.system_health import system_health_story
 
 
 class _BrowsingStory(system_health_story.SystemHealthStory):
   """Abstract base class for browsing stories.
@@ skipping 89 matching lines @@
 class FacebookDesktopStory(_NewsBrowsingStory):
   NAME = 'browse:social:facebook'
   URL = 'https://www.facebook.com/rihanna'
   ITEM_SELECTOR = '._4-eo'
   IS_SINGLE_PAGE_APP = True
   # Web-page-replay does not work for this website:
   # https://github.com/chromium/web-page-replay/issues/79.
   SUPPORTED_PLATFORMS = platforms.NO_PLATFORMS
 
 
+class FlipboardMobileStory(_NewsBrowsingStory):
+  NAME = 'browse:news:flipboard'
+  URL = 'https://flipboard.com/explore'
+  IS_SINGLE_PAGE_APP = True
+  ITEM_SELECTOR = '.grad-top'
+  ITEM_SCROLL_REPEAT = 4
+  SUPPORTED_PLATFORMS = platforms.MOBILE_ONLY
+
+
+class FlipboardDesktopStory(_NewsBrowsingStory):
+  NAME = 'browse:news:flipboard'
+  URL = 'https://flipboard.com/explore'
+  IS_SINGLE_PAGE_APP = True
+  ITEM_SELECTOR = '.cover-image'
+  SUPPORTED_PLATFORMS = platforms.DESKTOP_ONLY
+
+
 class HackerNewsStory(_NewsBrowsingStory):
   NAME = 'browse:news:hackernews'
   URL = 'https://news.ycombinator.com'
   ITEM_SELECTOR = '.athing .title > a'
 
 
 class NytimesMobileStory(_NewsBrowsingStory):
   """The third top website in http://www.alexa.com/topsites/category/News"""
   NAME = 'browse:news:nytimes'
   URL = 'http://mobile.nytimes.com'
@@ skipping 58 matching lines @@
   NAME = 'browse:news:washingtonpost'
   URL = 'https://www.washingtonpost.com/pwa'
   IS_SINGLE_PAGE_APP = True
   ITEM_SELECTOR = '.hed > a'
   SUPPORTED_PLATFORMS = platforms.MOBILE_ONLY
 
   def _DidLoadDocument(self, action_runner):
     # Close the popup window.
     action_runner.ClickElement(selector='.close')
     super(WashingtonPostMobileStory, self)._DidLoadDocument(action_runner)